1
|
Sanches E, Ho D, van de Looij Y, Aebi Toulotte A, Baud L, Bouteldja F, Barraud Q, Araneda R, Bleyenheuft Y, Brochard S, Kathe C, Courtine G, Sizonenko S. Early intensive rehabilitation reverses locomotor disruption, decrease brain inflammation and induces neuroplasticity following experimental Cerebral Palsy. Brain Behav Immun 2024; 121:303-316. [PMID: 39098438 DOI: 10.1016/j.bbi.2024.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Revised: 07/17/2024] [Accepted: 08/01/2024] [Indexed: 08/06/2024] Open
Abstract
BACKGROUND Cerebral Palsy (CP) is a major cause of motor and cognitive disability in children due to injury to the developing brain. Early intensive sensorimotor rehabilitation has been shown to change brain structure and reduce CP symptoms severity. We combined environmental enrichment (EE) and treadmill training (TT) to observe the effects of a one-week program of sensorimotor stimulation (EETT) in animals exposed to a CP model and explored possible mechanisms involved in the functional recovery. METHODS Pregnant Wistar rats were injected with Lipopolysaccharide (LPS - 200 µg/kg) intraperitoneally at embryonic days 18 and 19. At P0, pups of both sexes were exposed to 20' anoxia at 37 °C. From P2 to P21, hindlimbs were restricted for 16 h/day during the dark cycle. EETT lasted from P21 to P27. TT - 15 min/day at 7 cm/s. EE - 7 days in enriched cages with sensorimotor stimulus. Functional 3D kinematic gait analysis and locomotion were analyzed. At P28, brains were collected for ex-vivo MRI and histological assessment. Neurotrophins and key proteins involved in CNS function were assessed by western blotting. RESULTS CP model caused gross and skilled locomotor disruption and altered CNS neurochemistry. EETT reversed locomotor dysfunction with minor effects over gait kinematics. EETT also decreased brain inflammation and glial activation, preserved myelination, upregulated BDNF signaling and modulated the expression of proteins involved in excitatory synaptic function in the brain and spinal cord. CONCLUSIONS Using this translational approach based on intensive sensorimotor rehabilitation, we highlight pathways engaged in the early developmental processes improving neurological recovery observed in CP.
Collapse
Affiliation(s)
- Eduardo Sanches
- Division of Child Development and Growth, Department of Pediatrics, School of Medicine, University of Geneva, Geneva, Switzerland
| | - Dini Ho
- Division of Child Development and Growth, Department of Pediatrics, School of Medicine, University of Geneva, Geneva, Switzerland
| | - Yohan van de Looij
- Division of Child Development and Growth, Department of Pediatrics, School of Medicine, University of Geneva, Geneva, Switzerland; Center for Biomedical Imaging (CIBM), Animal Imaging Technology Section, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Audrey Aebi Toulotte
- Division of Child Development and Growth, Department of Pediatrics, School of Medicine, University of Geneva, Geneva, Switzerland
| | - Laetitia Baud
- Defitech Center for Interventional Neurotherapies (NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland; NeuroX Institute and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland; Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
| | - Farha Bouteldja
- Department of Fundamental Neurosciences, University of Lausanne (Unil), Switzerland
| | - Quentin Barraud
- Defitech Center for Interventional Neurotherapies (NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland; NeuroX Institute and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland; Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
| | - Rodrigo Araneda
- Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium; Exercise and Rehabilitation Science Institute, Faculty of Rehabilitation Science, Universidad Andres Bello, Santiago, Chile
| | - Yannick Bleyenheuft
- Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Sylvain Brochard
- Physical and Medical Rehabilitation Department, CHRU Brest, Brest, France; Paediatric Physical and Medical Rehabilitation Department, Fondation ILDYS, Brest, France; University of Western Brittany, Laboratory of Medical Information Processing, Inserm U1101, Brest, France
| | - Claudia Kathe
- Department of Fundamental Neurosciences, University of Lausanne (Unil), Switzerland
| | - Grégoire Courtine
- Defitech Center for Interventional Neurotherapies (NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland; NeuroX Institute and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland; Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
| | - Stéphane Sizonenko
- Division of Child Development and Growth, Department of Pediatrics, School of Medicine, University of Geneva, Geneva, Switzerland.
| |
Collapse
|
2
|
Lu CW, Lin TY, Chiu KM, Lee MY, Wang SJ. Gypenoside XVII Reduces Synaptic Glutamate Release and Protects against Excitotoxic Injury in Rats. Biomolecules 2024; 14:589. [PMID: 38785996 PMCID: PMC11118014 DOI: 10.3390/biom14050589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/15/2024] [Accepted: 05/14/2024] [Indexed: 05/25/2024] Open
Abstract
Excitotoxicity is a common pathological process in neurological diseases caused by excess glutamate. The purpose of this study was to evaluate the effect of gypenoside XVII (GP-17), a gypenoside monomer, on the glutamatergic system. In vitro, in rat cortical nerve terminals (synaptosomes), GP-17 dose-dependently decreased glutamate release with an IC50 value of 16 μM. The removal of extracellular Ca2+ or blockade of N-and P/Q-type Ca2+ channels and protein kinase A (PKA) abolished the inhibitory effect of GP-17 on glutamate release from cortical synaptosomes. GP-17 also significantly reduced the phosphorylation of PKA, SNAP-25, and synapsin I in cortical synaptosomes. In an in vivo rat model of glutamate excitotoxicity induced by kainic acid (KA), GP-17 pretreatment significantly prevented seizures and rescued neuronal cell injury and glutamate elevation in the cortex. GP-17 pretreatment decreased the expression levels of sodium-coupled neutral amino acid transporter 1, glutamate synthesis enzyme glutaminase and vesicular glutamate transporter 1 but increased the expression level of glutamate metabolism enzyme glutamate dehydrogenase in the cortex of KA-treated rats. In addition, the KA-induced alterations in the N-methyl-D-aspartate receptor subunits GluN2A and GluN2B in the cortex were prevented by GP-17 pretreatment. GP-17 also prevented the KA-induced decrease in cerebral blood flow and arginase II expression. These results suggest that (i) GP-17, through the suppression of N- and P/Q-type Ca2+ channels and consequent PKA-mediated SNAP-25 and synapsin I phosphorylation, reduces glutamate exocytosis from cortical synaptosomes; and (ii) GP-17 has a neuroprotective effect on KA-induced glutamate excitotoxicity in rats through regulating synaptic glutamate release and cerebral blood flow.
Collapse
Affiliation(s)
- Cheng-Wei Lu
- Department of Anesthesiology, Far-Eastern Memorial Hospital, New Taipei 22060, Taiwan; (C.-W.L.); (T.-Y.L.)
- Department of Mechanical Engineering, Yuan Ze University, Taoyuan 32003, Taiwan
| | - Tzu-Yu Lin
- Department of Anesthesiology, Far-Eastern Memorial Hospital, New Taipei 22060, Taiwan; (C.-W.L.); (T.-Y.L.)
- Department of Mechanical Engineering, Yuan Ze University, Taoyuan 32003, Taiwan
| | - Kuan-Ming Chiu
- Division of Cardiovascular Surgery, Cardiovascular Center, Far-Eastern Memorial Hospital, New Taipei 22060, Taiwan;
- Department of Electrical Engineering, Yuan Ze University, Taoyuan 32003, Taiwan
| | - Ming-Yi Lee
- Department of Medical Research, Far-Eastern Memorial Hospital, New Taipei 22060, Taiwan;
| | - Su-Jane Wang
- School of Medicine, Fu Jen Catholic University, New Taipei 24205, Taiwan
- Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan 33303, Taiwan
| |
Collapse
|
3
|
Ariani A, Khotimah H, Sulistyarini A, Daniaridevi AS. Centella asiatica extract ameliorates deoxygenation-induced neurological dysfunction in zebrafish larvae. Open Vet J 2024; 14:1154-1160. [PMID: 38938421 PMCID: PMC11199753 DOI: 10.5455/ovj.2024.v14.i5.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Accepted: 04/16/2024] [Indexed: 06/29/2024] Open
Abstract
Background Oxygen deprivation (OD) is a critical condition that can lead to brain damage and even death. Current hypoxia management approaches are limited in effectiveness. Centella asiatica (CA), known for its neuroprotective properties, offers a potential alternative for OD treatment. Aims This study aims to investigate the neuroprotective effects of CA on the expression of brain-derived neurotrophic factor (BDNF) and vesicular glutamate transporter 1 (VGLUT1) in zebrafish larvae under oxygen-deficient conditions. Methods Zebrafish embryos were subjected to low oxygen levels (1.5 mg/l) 0-2 hours post-fertilization (hpf) until 3 days post-fertilization (dpf), simulating the early stages of OD. Subsequent treatment involved varying concentrations of CA (1.25-5 µg/ml) up to 9 days post-fertilization. The expression levels of BDNF and VGLUT1 were measured using PCR methods. Statistical analysis was conducted using a two-way analysis of variance to evaluate the impact of CA on the expression of BDNF and VGLUT1 in zebrafish larvae aged 3 and 9 dpf in oxygen-deprived conditions. Results CA significantly influenced the expression of BDNF and VGLUT1 under OD (p < 0.001). An increase in BDNF expression (p < 0.001) and a decrease in VGLUT1 (p < 0.01) were observed in zebrafish larvae experiencing OD and treated with CA. There was no significant difference in BDNF and VGLUT1 expression across age variations in zebrafish larvae at 3 dpf and 9 dpf in the treatment groups (p > 0.05). CA concentration of 2.5 µg/ml effectively enhanced BDNF and reduced VGLUT1 in 3-9 dpf zebrafish larvae. Conclusion CA demonstrates potential as a neuroprotective agent, modulating increased BDNF expression and reduced VGLUT1 under OD conditions. These findings lay a foundation for further research in developing therapies for oxygen deficiency.
Collapse
Affiliation(s)
- Ariani Ariani
- Department of Pediatrics, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
- Saiful Anwar General Hospital, Malang, Indonesia
| | - Husnul Khotimah
- Department of Pharmacology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
| | - Arum Sulistyarini
- Bachelor of Medicine, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
| | | |
Collapse
|
4
|
Vaglio-Garro A, Kozlov AV, Smirnova YD, Weidinger A. Pathological Interplay between Inflammation and Mitochondria Aggravates Glutamate Toxicity. Int J Mol Sci 2024; 25:2276. [PMID: 38396952 PMCID: PMC10889519 DOI: 10.3390/ijms25042276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 02/06/2024] [Accepted: 02/09/2024] [Indexed: 02/25/2024] Open
Abstract
Mitochondrial dysfunction and glutamate toxicity are associated with neural disorders, including brain trauma. A review of the literature suggests that toxic and transmission actions of neuronal glutamate are spatially and functionally separated. The transmission pathway utilizes synaptic GluN2A receptors, rapidly released pool of glutamate, evoked release of glutamate mediated by Synaptotagmin 1 and the amount of extracellular glutamate regulated by astrocytes. The toxic pathway utilizes extrasynaptic GluN2B receptors and a cytoplasmic pool of glutamate, which results from the spontaneous release of glutamate mediated by Synaptotagmin 7 and the neuronal 2-oxoglutarate dehydrogenase complex (OGDHC), a tricarboxylic acid (TCA) cycle enzyme. Additionally, the inhibition of OGDHC observed upon neuro-inflammation is due to an excessive release of reactive oxygen/nitrogen species by immune cells. The loss of OGDHC inhibits uptake of glutamate by mitochondria, thus facilitating its extracellular accumulation and stimulating toxic glutamate pathway without affecting transmission. High levels of extracellular glutamate lead to dysregulation of intracellular redox homeostasis and cause ferroptosis, excitotoxicity, and mitochondrial dysfunction. The latter affects the transmission pathway demanding high-energy supply and leading to cell death. Mitochondria aggravate glutamate toxicity due to impairments in the TCA cycle and become a victim of glutamate toxicity, which disrupts oxidative phosphorylation. Thus, therapies targeting the TCA cycle in neurological disorders may be more efficient than attempting to preserve mitochondrial oxidative phosphorylation.
Collapse
Affiliation(s)
- Annette Vaglio-Garro
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, 1200 Vienna, Austria; (A.V.-G.); (Y.D.S.); (A.W.)
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
| | - Andrey V. Kozlov
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, 1200 Vienna, Austria; (A.V.-G.); (Y.D.S.); (A.W.)
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
| | - Yuliya D. Smirnova
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, 1200 Vienna, Austria; (A.V.-G.); (Y.D.S.); (A.W.)
- Laboratory of Metagenomics and Food Biotechnology, Voronezh State University of Engineering Technologies, 394036 Voronezh, Russia
| | - Adelheid Weidinger
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, 1200 Vienna, Austria; (A.V.-G.); (Y.D.S.); (A.W.)
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
| |
Collapse
|
5
|
Akçay G, Aslan M, Kipmen Korgun D, Çeker T, Akan E, Derin N. Effects of transcranial direct current stimulation on the glutamatergic pathway in the male rat hippocampus after experimental focal cerebral ischemia. J Neurosci Res 2024; 102:e25247. [PMID: 37800665 DOI: 10.1002/jnr.25247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 08/22/2023] [Accepted: 09/10/2023] [Indexed: 10/07/2023]
Abstract
This study aimed to assess the focal cerebral ischemia-induced changes in learning and memory together with glutamatergic pathway in rats and the effects of treatment of the animals with transcranial Direct Current Stimulation (tDCS). One hundred male rats were divided into five groups as sham, tDCS, Ischemia/Reperfusion (IR), IR + tDCS, and IR + E-tDCS groups. Learning, memory, and locomotor activity functions were evaluated by behavioral experiments in rats. Glutamate and glutamine levels, alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionate receptor (AMPAR1), N-Methyl-D-Aspartate receptors (NMDAR1 and NMDAR2A), vesicular glutamate transporter-1 (VGLUT-1), and excitatory amino acid transporters (EAAT1-3) mRNA expressions in hippocampus tissues were measured. Ischemic areas were analyzed by TTC staining. The increase was observed in IR + tDCS, and IR + E-tDCS groups compared to the IR group while a significant decrease was observed in IR group compared to the sham in the locomotor activity, learning, and memory tests. While glutamate and glutamine levels, AMPAR1, NMDAR1, NMDAR2A, VGLUT1, and EAAT1 mRNA expressions were significantly higher in IR group compared to the sham group, it was found to be significantly lower in IR + tDCS and IR + E-tDCS groups compared to the IR group. EAAT2 and EAAT3 mRNA expressions were significantly higher in IR + tDCS and IR + E-tDCS groups compared to the IR group. Ischemic areas were significantly decreased in IR + tDCS and IR + E-tDCS groups compared to the IR group. Current results suggest that tDCS application after ischemia improves learning and memory disorders and these effects of tDCS may be provided through transporters that regulate glutamate levels.
Collapse
Affiliation(s)
- Guven Akçay
- Faculty of Medicine, Department of Biophysics, Hitit University, Çorum, Turkey
| | - Mutay Aslan
- Faculty of Medicine, Department of Biochemistry, Akdeniz University, Antalya, Turkey
| | - Dijle Kipmen Korgun
- Faculty of Medicine, Department of Biochemistry, Akdeniz University, Antalya, Turkey
| | - Tugçe Çeker
- Faculty of Medicine, Department of Biochemistry, Akdeniz University, Antalya, Turkey
| | - Ezgi Akan
- Faculty of Medicine, Department of Biochemistry, Akdeniz University, Antalya, Turkey
| | - Narin Derin
- Faculty of Medicine, Department of Biophysics, Akdeniz University, Antalya, Turkey
| |
Collapse
|
6
|
Melo GM, Capucho AM, Sacramento JF, Ponce-de-Leão J, Fernandes MV, Almeida IF, Martins FO, Conde SV. Overnutrition during Pregnancy and Lactation Induces Gender-Dependent Dysmetabolism in the Offspring Accompanied by Heightened Stress and Anxiety. Nutrients 2023; 16:67. [PMID: 38201896 PMCID: PMC10781034 DOI: 10.3390/nu16010067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 12/18/2023] [Accepted: 12/20/2023] [Indexed: 01/12/2024] Open
Abstract
Maternal obesity and gestational diabetes predispose the next generation to metabolic disturbances. Moreover, the lactation phase also stands as a critical phase for metabolic programming. Nevertheless, the precise mechanisms originating these changes remain unclear. Here, we investigate the consequences of a maternal lipid-rich diet during gestation and lactation and its impact on metabolism and behavior in the offspring. Two experimental groups of Wistar female rats were used: a control group (NC) that was fed a standard diet during the gestation and lactation periods and an overnutrition group that was fed a high-fat diet (HF, 60% lipid-rich) during the same phases. The offspring were analyzed at postnatal days 21 and 28 and at 2 months old (PD21, PD28, and PD60) for their metabolic profiles (weight, fasting glycemia insulin sensitivity, and glucose tolerance) and euthanized for brain collection to evaluate metabolism and inflammation in the hypothalamus, hippocampus, and prefrontal cortex using Western blot markers of synaptic dynamics. At 2 months old, behavioral tests for anxiety, stress, cognition, and food habits were conducted. We observed that the female offspring born from HF mothers exhibited increased weight gain and decreased glucose tolerance that attenuated with age. In the offspring males, weight gain increased at P21 and worsened with age, while glucose tolerance remained unchanged. The offspring of the HF mothers exhibited elevated levels of anxiety and stress during behavioral tests, displaying decreased predisposition for curiosity compared to the NC group. In addition, the offspring from mothers with HF showed increased food consumption and a lower tendency towards food-related aggression. We conclude that exposure to an HF diet during pregnancy and lactation induces dysmetabolism in the offspring and is accompanied by heightened stress and anxiety. There was sexual dimorphism in the metabolic traits but not behavioral phenotypes.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Silvia V. Conde
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Rua Camara Pestana, 6, Edificio 2, 1150-082 Lisboa, Portugal; (G.M.M.); (A.M.C.); (J.F.S.); (J.P.-d.-L.); (M.V.F.); (I.F.A.); (F.O.M.)
| |
Collapse
|
7
|
Weidinger A, Milivojev N, Hosmann A, Duvigneau JC, Szabo C, Törö G, Rauter L, Vaglio-Garro A, Mkrtchyan GV, Trofimova L, Sharipov RR, Surin AM, Krasilnikova IA, Pinelis VG, Tretter L, Moldzio R, Bayır H, Kagan VE, Bunik VI, Kozlov AV. Oxoglutarate dehydrogenase complex controls glutamate-mediated neuronal death. Redox Biol 2023; 62:102669. [PMID: 36933393 PMCID: PMC10031542 DOI: 10.1016/j.redox.2023.102669] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/03/2023] [Accepted: 03/10/2023] [Indexed: 03/14/2023] Open
Abstract
Brain injury is accompanied by neuroinflammation, accumulation of extracellular glutamate and mitochondrial dysfunction, all of which cause neuronal death. The aim of this study was to investigate the impact of these mechanisms on neuronal death. Patients from the neurosurgical intensive care unit suffering aneurysmal subarachnoid hemorrhage (SAH) were recruited retrospectively from a respective database. In vitro experiments were performed in rat cortex homogenate, primary dissociated neuronal cultures, B35 and NG108-15 cell lines. We employed methods including high resolution respirometry, electron spin resonance, fluorescent microscopy, kinetic determination of enzymatic activities and immunocytochemistry. We found that elevated levels of extracellular glutamate and nitric oxide (NO) metabolites correlated with poor clinical outcome in patients with SAH. In experiments using neuronal cultures we showed that the 2-oxoglutarate dehydrogenase complex (OGDHC), a key enzyme of the glutamate-dependent segment of the tricarboxylic acid (TCA) cycle, is more susceptible to the inhibition by NO than mitochondrial respiration. Inhibition of OGDHC by NO or by succinyl phosphonate (SP), a highly specific OGDHC inhibitor, caused accumulation of extracellular glutamate and neuronal death. Extracellular nitrite did not substantially contribute to this NO action. Reactivation of OGDHC by its cofactor thiamine (TH) reduced extracellular glutamate levels, Ca2+ influx into neurons and cell death rate. Salutary effect of TH against glutamate toxicity was confirmed in three different cell lines. Our data suggest that the loss of control over extracellular glutamate, as described here, rather than commonly assumed impaired energy metabolism, is the critical pathological manifestation of insufficient OGDHC activity, leading to neuronal death.
Collapse
Affiliation(s)
- Adelheid Weidinger
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, Vienna, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Nadja Milivojev
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, Vienna, Austria
| | - Arthur Hosmann
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - J Catharina Duvigneau
- Institute for Medical Biochemistry, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Csaba Szabo
- University of Fribourg, Section of Science and Medicine, Department of Oncology, Microbiology and Immunology, Section of Pharmacology, Fribourg, Switzerland; Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX, USA
| | - Gabor Törö
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX, USA
| | - Laurin Rauter
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, Vienna, Austria
| | - Annette Vaglio-Garro
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, Vienna, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Garik V Mkrtchyan
- A. N. Belozersky Institute of Physicochemical Biology, Lomonosov Moscow State University, 119234, Moscow, Russia
| | - Lidia Trofimova
- Biological Faculty, Department of Biophysics, Lomonosov Moscow State University, Moscow, Russia
| | - Rinat R Sharipov
- Institute of General Pathology and Pathophysiology, Laboratory of Fundamental and Applied Problems of Pain, Moscow, Russia
| | - Alexander M Surin
- Institute of General Pathology and Pathophysiology, Laboratory of Fundamental and Applied Problems of Pain, Moscow, Russia; National Medical Research Center of Children's Health, Russian Ministry of Health, Laboratory of Neurobiology and Brain Development, Moscow, Russia
| | - Irina A Krasilnikova
- National Medical Research Center of Children's Health, Russian Ministry of Health, Laboratory of Neurobiology and Brain Development, Moscow, Russia
| | - Vsevolod G Pinelis
- National Medical Research Center of Children's Health, Russian Ministry of Health, Laboratory of Neurobiology and Brain Development, Moscow, Russia
| | - Laszlo Tretter
- Department of Biochemistry, Semmelweis University, Budapest, Hungary
| | - Rudolf Moldzio
- Institute for Medical Biochemistry, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Hülya Bayır
- Departments of Environmental and Occupational Health, Pharmacology and Chemical Biology, Chemistry and Center for Free Radical and Antioxidant Health University of Pittsburgh, Pittsburgh, PA, USA; Department of Critical Care Medicine, Safar Center for Resuscitation Research, Children's Neuroscience Institute, Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA, USA
| | - Valerian E Kagan
- Departments of Environmental and Occupational Health, Pharmacology and Chemical Biology, Chemistry and Center for Free Radical and Antioxidant Health University of Pittsburgh, Pittsburgh, PA, USA
| | - Victoria I Bunik
- A. N. Belozersky Institute of Physicochemical Biology, Lomonosov Moscow State University, 119234, Moscow, Russia; Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia; Department of Biochemistry, Sechenov University, Moscow, Russia
| | - Andrey V Kozlov
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, Vienna, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria.
| |
Collapse
|
8
|
Inhibition of Vesicular Glutamate Transporters (VGLUTs) with Chicago Sky Blue 6B Before Focal Cerebral Ischemia Offers Neuroprotection. Mol Neurobiol 2023; 60:3130-3146. [PMID: 36802054 PMCID: PMC10122628 DOI: 10.1007/s12035-023-03259-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 02/07/2023] [Indexed: 02/21/2023]
Abstract
Brain ischemia is one of the leading causes of death and long-term disability in the world. Interruption of the blood supply to the brain is a direct stimulus for many pathological events. The massive vesicular release of glutamate (Glu) after ischemia onset induces excitotoxicity, which is a potent stress on neurons. Loading of presynaptic vesicles with Glu is the first step of glutamatergic neurotransmission. Vesicular glutamate transporters 1, 2, and 3 (VGLUT1, 2, and 3) are the main players involved in filling presynaptic vesicles with Glu. VGLUT1 and VGLUT2 are expressed mainly in glutamatergic neurons. Therefore, the possibility of pharmacological modulation to prevent ischemia-related brain damage is attractive. In this study, we aimed to determine the effect of focal cerebral ischemia on the spatiotemporal expression of VGLUT1 and VGLUT2 in rats. Next, we investigated the influence of VGLUT inhibition with Chicago Sky Blue 6B (CSB6B) on Glu release and stroke outcome. The effect of CSB6B pretreatment on infarct volume and neurological deficit was compared with a reference model of ischemic preconditioning. The results of this study indicate that ischemia upregulated the expression of VGLUT1 in the cerebral cortex and in the dorsal striatum 3 days after ischemia onset. The expression of VGLUT2 was elevated in the dorsal striatum and in the cerebral cortex 24 h and 3 days after ischemia, respectively. Microdialysis revealed that pretreatment with CSB6B significantly reduced the extracellular Glu concentration. Altogether, this study shows that inhibition of VGLUTs might be a promising therapeutic strategy for the future.
Collapse
|
9
|
Craeghs L, Callaerts-Vegh Z, Verslegers M, Van der Jeugd A, Govaerts K, Dresselaers T, Wogensen E, Verreet T, Moons L, Benotmane MA, Himmelreich U, D'Hooge R. Prenatal Radiation Exposure Leads to Higher-Order Telencephalic Dysfunctions in Adult Mice That Coincide with Reduced Synaptic Plasticity and Cerebral Hypersynchrony. Cereb Cortex 2021; 32:3525-3541. [PMID: 34902856 DOI: 10.1093/cercor/bhab431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 11/14/2022] Open
Abstract
Higher-order telencephalic circuitry has been suggested to be especially vulnerable to irradiation or other developmentally toxic impact. This report details the adult effects of prenatal irradiation at a sensitive time point on clinically relevant brain functions controlled by telencephalic regions, hippocampus (HPC), and prefrontal cortex (PFC). Pregnant C57Bl6/J mice were whole-body irradiated at embryonic day 11 (start of neurogenesis) with X-ray intensities of 0.0, 0.5, or 1.0 Gy. Female offspring completed a broad test battery of HPC-/PFC-controlled tasks that included cognitive performance, fear extinction, exploratory, and depression-like behaviors. We examined neural functions that are mechanistically related to these behavioral and cognitive changes, such as hippocampal field potentials and long-term potentiation, functional brain connectivity (by resting-state functional magnetic resonance imaging), and expression of HPC vesicular neurotransmitter transporters (by immunohistochemical quantification). Prenatally exposed mice displayed several higher-order dysfunctions, such as decreased nychthemeral activity, working memory defects, delayed extinction of threat-evoked response suppression as well as indications of perseverative behavior. Electrophysiological examination indicated impaired hippocampal synaptic plasticity. Prenatal irradiation also induced cerebral hypersynchrony and increased the number of glutamatergic HPC terminals. These changes in brain connectivity and plasticity could mechanistically underlie the irradiation-induced defects in higher telencephalic functions.
Collapse
Affiliation(s)
- Livine Craeghs
- Department of Brain & Cognition, Research Group Biological Psychology, University of Leuven (KU Leuven), Leuven 3000, Belgium
| | - Zsuzsanna Callaerts-Vegh
- Department of Brain & Cognition, Research Group Biological Psychology, University of Leuven (KU Leuven), Leuven 3000, Belgium
| | - Mieke Verslegers
- Department of Radiobiology, Institute for Environmental Health and Safety, Nuclear Research Center (SCK CEN), Mol 2400, Belgium
| | - Ann Van der Jeugd
- Department of Brain & Cognition, Research Group Biological Psychology, University of Leuven (KU Leuven), Leuven 3000, Belgium
| | - Kristof Govaerts
- Department of Imaging & Pathology, Research Group Biomedical MRI, University of Leuven (KU Leuven), Leuven 3000, Belgium
| | - Tom Dresselaers
- Department of Imaging & Pathology, Research Group Biomedical MRI, University of Leuven (KU Leuven), Leuven 3000, Belgium
| | - Elise Wogensen
- Department of Brain & Cognition, Research Group Biological Psychology, University of Leuven (KU Leuven), Leuven 3000, Belgium
| | - Tine Verreet
- Department of Radiobiology, Institute for Environmental Health and Safety, Nuclear Research Center (SCK CEN), Mol 2400, Belgium
| | - Lieve Moons
- Department of Biology, Research Group Neural Circuit Development and Regeneration, University of Leuven (KU Leuven), Leuven 3000, Belgium
| | - Mohammed A Benotmane
- Department of Radiobiology, Institute for Environmental Health and Safety, Nuclear Research Center (SCK CEN), Mol 2400, Belgium
| | - Uwe Himmelreich
- Department of Imaging & Pathology, Research Group Biomedical MRI, University of Leuven (KU Leuven), Leuven 3000, Belgium
| | - Rudi D'Hooge
- Department of Brain & Cognition, Research Group Biological Psychology, University of Leuven (KU Leuven), Leuven 3000, Belgium
| |
Collapse
|
10
|
Li X, Chien C, Han Y, Sun Z, Chen X, Dickman D. Autocrine inhibition by a glutamate-gated chloride channel mediates presynaptic homeostatic depression. SCIENCE ADVANCES 2021; 7:eabj1215. [PMID: 34851664 PMCID: PMC8635443 DOI: 10.1126/sciadv.abj1215] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 10/14/2021] [Indexed: 06/13/2023]
Abstract
Homeostatic modulation of presynaptic neurotransmitter release is a fundamental form of plasticity that stabilizes neural activity, where presynaptic homeostatic depression (PHD) can adaptively diminish synaptic strength. PHD has been proposed to operate through an autocrine mechanism to homeostatically depress release probability in response to excess glutamate release at the Drosophila neuromuscular junction. This model implies the existence of a presynaptic glutamate autoreceptor. We systematically screened all neuronal glutamate receptors in the fly genome and identified the glutamate-gated chloride channel (GluClα) to be required for the expression of PHD. Pharmacological, genetic, and Ca2+ imaging experiments demonstrate that GluClα acts locally at axonal terminals to drive PHD. Unexpectedly, GluClα localizes and traffics with synaptic vesicles to drive presynaptic inhibition through an activity-dependent anionic conductance. Thus, GluClα operates as both a sensor and effector of PHD to adaptively depress neurotransmitter release through an elegant autocrine inhibitory signaling mechanism at presynaptic terminals.
Collapse
Affiliation(s)
- Xiling Li
- Department of Neurobiology, University of Southern California, Los Angeles, CA, 90089, USA
- USC Neuroscience Graduate Program, Los Angeles, CA, 90089, USA
| | - Chun Chien
- Department of Neurobiology, University of Southern California, Los Angeles, CA, 90089, USA
- USC Neuroscience Graduate Program, Los Angeles, CA, 90089, USA
| | - Yifu Han
- Department of Neurobiology, University of Southern California, Los Angeles, CA, 90089, USA
- USC Neuroscience Graduate Program, Los Angeles, CA, 90089, USA
| | - Zihan Sun
- Department of Neurobiology, University of Southern California, Los Angeles, CA, 90089, USA
| | - Xun Chen
- Department of Neurobiology, University of Southern California, Los Angeles, CA, 90089, USA
- USC Neuroscience Graduate Program, Los Angeles, CA, 90089, USA
| | - Dion Dickman
- Department of Neurobiology, University of Southern California, Los Angeles, CA, 90089, USA
| |
Collapse
|
11
|
Jeong J, Lee J, Kim JH, Lim C. Metabolic flux from the Krebs cycle to glutamate transmission tunes a neural brake on seizure onset. PLoS Genet 2021; 17:e1009871. [PMID: 34714823 PMCID: PMC8555787 DOI: 10.1371/journal.pgen.1009871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 10/11/2021] [Indexed: 01/18/2023] Open
Abstract
Kohlschütter-Tönz syndrome (KTS) manifests as neurological dysfunctions, including early-onset seizures. Mutations in the citrate transporter SLC13A5 are associated with KTS, yet their underlying mechanisms remain elusive. Here, we report that a Drosophila SLC13A5 homolog, I'm not dead yet (Indy), constitutes a neurometabolic pathway that suppresses seizure. Loss of Indy function in glutamatergic neurons caused "bang-induced" seizure-like behaviors. In fact, glutamate biosynthesis from the citric acid cycle was limiting in Indy mutants for seizure-suppressing glutamate transmission. Oral administration of the rate-limiting α-ketoglutarate in the metabolic pathway rescued low glutamate levels in Indy mutants and ameliorated their seizure-like behaviors. This metabolic control of the seizure susceptibility was mapped to a pair of glutamatergic neurons, reversible by optogenetic controls of their activity, and further relayed onto fan-shaped body neurons via the ionotropic glutamate receptors. Accordingly, our findings reveal a micro-circuit that links neural metabolism to seizure, providing important clues to KTS-associated neurodevelopmental deficits.
Collapse
Affiliation(s)
- Jiwon Jeong
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Jongbin Lee
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Ji-hyung Kim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Chunghun Lim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
- * E-mail:
| |
Collapse
|
12
|
Li X, Wang W, Yan J, Zeng F. Glutamic Acid Transporters: Targets for Neuroprotective Therapies in Parkinson's Disease. Front Neurosci 2021; 15:678154. [PMID: 34220434 PMCID: PMC8242205 DOI: 10.3389/fnins.2021.678154] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 05/07/2021] [Indexed: 12/21/2022] Open
Abstract
Parkinson's disease (PD) is a common neurodegenerative disease in middle-aged and elderly individuals. At present, no effective drug has been developed to treat PD. Although a variety of drugs exist for the symptomatic treatment of PD, they all have strong side effects. Most studies on PD mainly focus on dopaminergic neurons. This review highlights the function of glutamic acid transporters (GLTs), including excitatory amino acid transporters (EAATs) and vesicular glutamate transporters (VGLUTs), during the development of PD. In addition, using bioinformatics, we compared the expression of different types of glutamate transporter genes in the cingulate gyrus of PD patients and healthy controls. More importantly, we suggest that the functional roles of glutamate transporters may prove beneficial in the treatment of PD. In summary, VGLUTs and EAATs may be potential targets in the treatment of PD. VGLUTs and EAATs can be used as clinical drug targets to achieve better efficacy. Through this review article, we hope to enable future researchers to improve the condition of PD patients.
Collapse
Affiliation(s)
- Xiang Li
- Department of Biochemistry and Molecular Biology, School of Basic Medical Science, Southwest Medical University, Luzhou, China
| | - Wenjun Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Science, Southwest Medical University, Luzhou, China.,Institute for Cancer Medicine and School of Basic Medical Sciences, Southwest Medical University, Luzhou, China
| | - Jianghong Yan
- Department of Biochemistry and Molecular Biology, School of Basic Medical Science, Southwest Medical University, Luzhou, China
| | - Fancai Zeng
- Department of Biochemistry and Molecular Biology, School of Basic Medical Science, Southwest Medical University, Luzhou, China
| |
Collapse
|
13
|
Goel P, Dickman D. Synaptic homeostats: latent plasticity revealed at the Drosophila neuromuscular junction. Cell Mol Life Sci 2021; 78:3159-3179. [PMID: 33449150 PMCID: PMC8044042 DOI: 10.1007/s00018-020-03732-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 11/19/2020] [Accepted: 12/04/2020] [Indexed: 12/11/2022]
Abstract
Homeostatic signaling systems are fundamental forms of biological regulation that maintain stable functionality in a changing environment. In the nervous system, synapses are crucial substrates for homeostatic modulation, serving to establish, maintain, and modify the balance of excitation and inhibition. Synapses must be sufficiently flexible to enable the plasticity required for learning and memory but also endowed with the stability to last a lifetime. In response to the processes of development, growth, remodeling, aging, and disease that challenge synapses, latent forms of adaptive plasticity become activated to maintain synaptic stability. In recent years, new insights into the homeostatic control of synaptic function have been achieved using the powerful Drosophila neuromuscular junction (NMJ). This review will focus on work over the past 10 years that has illuminated the cellular and molecular mechanisms of five homeostats that operate at the fly NMJ. These homeostats adapt to loss of postsynaptic neurotransmitter receptor functionality, glutamate imbalance, axonal injury, as well as aberrant synaptic growth and target innervation. These diverse homeostats work independently yet can be simultaneously expressed to balance neurotransmission. Growing evidence from this model glutamatergic synapse suggests these ancient homeostatic signaling systems emerged early in evolution and are fundamental forms of plasticity that also function to stabilize mammalian cholinergic NMJs and glutamatergic central synapses.
Collapse
Affiliation(s)
- Pragya Goel
- Department of Neurobiology, University of Southern California, Los Angeles, CA, 90089, USA
| | - Dion Dickman
- Department of Neurobiology, University of Southern California, Los Angeles, CA, 90089, USA.
| |
Collapse
|
14
|
Kim S, Kim HK, Baek AR, Sung B, Yang BW, Kim YH, Lee JJ, Yang JU, Shin CH, Jung H, Kim M, Cho AE, Lee T, Chang Y. Rose bengal conjugated gadolinium complex as a new multimodal imaging agent targeting presynaptic vesicular glutamate transporters. J IND ENG CHEM 2021. [DOI: 10.1016/j.jiec.2020.12.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
15
|
Magalhães-Gomes MPS, Camargos W, Valadão PAC, Garcias RS, Rodrigues HA, Andrade JN, Teixeira VP, Naves LA, Cavalcante WLG, Gallaci M, Guatimosim S, Prado VF, Prado MAM, Guatimosim C. Increased Cholinergic Tone Causes Pre-synaptic Neuromuscular Degeneration and is Associated with Impaired Diaphragm Function. Neuroscience 2021; 460:31-42. [PMID: 33548369 DOI: 10.1016/j.neuroscience.2020.12.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 12/08/2020] [Accepted: 12/17/2020] [Indexed: 11/25/2022]
Abstract
In vertebrates, muscle activity is dependent on acetylcholine (ACh) released from neuromuscular junctions (NMJs), and changes in cholinergic neurotransmission are linked to a variety of neuromuscular diseases, including congenital myasthenic syndromes (CMS). The storage and release of ACh depends on the activity of the Vesicular Acetylcholine Transporter (VAChT), a rate-limiting step for cholinergic neurotransmission whose loss of function mutations was shown to cause human congenital myasthenia. However, we know much less about increased VAChT activity, due to copy number variations, for example. Therefore, here we investigated the impact of increased VAChT expression and consequently ACh levels at the synaptic cleft of the diaphragm NMJs. We analyzed structure and function of nerve and muscles from a mouse model of cholinergic hyperfunction (ChAT-ChR2-EYFP) with increased expression of VAChT. Our results showed a significant increase of ACh released under evoked stimuli. However, we observed deleterious changes in synaptic vesicles cycle (impaired endocytosis and decrease in vesicles number), together with structural alterations of NMJs. Interestingly, ultrastructure analyses showed that synaptic vesicles from ChAT-ChR2-EYFP mice NMJs were larger, which might be related to increased ACh load. We also observed that these larger synaptic vesicles were less rounded in comparison with control. Finally, we showed that ChAT-ChR2-EYFP mice NMJs have compromised safety factor, possible due to the structural alterations we described. These findings reveal that physiological cholinergic activity is important to maintain the structure and function of the neuromuscular system and help to understand some of the neuromuscular adverse effects experienced by chronically increased NMJ neurotransmission, such as individuals treated with cholinesterase inhibitors.
Collapse
Affiliation(s)
- Matheus P S Magalhães-Gomes
- Departamento de Morfologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil; Departamento de Medicina, Faculdade Ciências Médicas de Minas Gerais, FCMMG, Belo Horizonte, MG, Brazil.
| | - Wallace Camargos
- Departamento de Fisiologia e Biofísica, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Priscila A C Valadão
- Departamento de Morfologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Rubens S Garcias
- Departamento de Morfologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Hermann A Rodrigues
- Departamento de Ciências Básicas da Vida, Instituto de Ciências da Vida, Universidade Federal de Juiz de Fora, Campus Governador Valadares, UFJF, Governador Valadares, MG, Brazil
| | - Jéssica N Andrade
- Departamento de Morfologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Vanessa P Teixeira
- Departamento de Fisiologia e Biofísica, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Lígia A Naves
- Departamento de Fisiologia e Biofísica, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Walter L G Cavalcante
- Departamento de Farmacologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Marcia Gallaci
- Departamento de Farmacologia, Instituto de Biociências, UNESP, Distrito de Rubião Jr., Botucatu, São Paulo, Brazil
| | - Silvia Guatimosim
- Departamento de Fisiologia e Biofísica, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Vânia F Prado
- Robarts Research Institute and Department of Physiology and Pharmacology and Anatomy & Cell Biology, University of Western Ontario, London, ON, Canada
| | - Marco A M Prado
- Robarts Research Institute and Department of Physiology and Pharmacology and Anatomy & Cell Biology, University of Western Ontario, London, ON, Canada
| | - Cristina Guatimosim
- Departamento de Morfologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
| |
Collapse
|
16
|
Wang M, Witvliet D, Wu M, Kang L, Shao Z. Temperature regulates synaptic subcellular specificity mediated by inhibitory glutamate signaling. PLoS Genet 2021; 17:e1009295. [PMID: 33428618 PMCID: PMC7822552 DOI: 10.1371/journal.pgen.1009295] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 01/22/2021] [Accepted: 12/05/2020] [Indexed: 01/13/2023] Open
Abstract
Environmental factors such as temperature affect neuronal activity and development. However, it remains unknown whether and how they affect synaptic subcellular specificity. Here, using the nematode Caenorhabditis elegans AIY interneurons as a model, we found that high cultivation temperature robustly induces defects in synaptic subcellular specificity through glutamatergic neurotransmission. Furthermore, we determined that the functional glutamate is mainly released by the ASH sensory neurons and sensed by two conserved inhibitory glutamate-gated chloride channels GLC-3 and GLC-4 in AIY. Our work not only presents a novel neurotransmission-dependent mechanism underlying the synaptic subcellular specificity, but also provides a potential mechanistic insight into high-temperature-induced neurological defects.
Collapse
Affiliation(s)
- Mengqing Wang
- Department of Neurosurgery, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Daniel Witvliet
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Mengting Wu
- Department of Neurosurgery, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Lijun Kang
- Department of Neurobiology and Department of Neurosurgery of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Zhiyong Shao
- Department of Neurosurgery, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| |
Collapse
|
17
|
Vesicular neurotransmitter transporters in Drosophila melanogaster. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183308. [PMID: 32305263 DOI: 10.1016/j.bbamem.2020.183308] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 04/09/2020] [Accepted: 04/10/2020] [Indexed: 12/11/2022]
Abstract
Drosophila melanogaster express vesicular transporters for the storage of neurotransmitters acetylcholine, biogenic amines, GABA, and glutamate. The large array of powerful molecular-genetic tools available in Drosophila enhances the use of this model organism for studying transporter function and regulation.
Collapse
|
18
|
Saha P, Gupta R, Sen T, Sen N. Histone Deacetylase 4 Downregulation Elicits Post-Traumatic Psychiatric Disorders through Impairment of Neurogenesis. J Neurotrauma 2019; 36:3284-3296. [PMID: 31169064 DOI: 10.1089/neu.2019.6373] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
An enduring deficit in neurogenesis largely contributes to the development of severe post-traumatic psychiatric disorders such as anxiety, depression, and memory impairment following traumatic brain injury (TBI); however, the mechanism remains obscure. Here we have shown that an imbalance in the generation of γ-aminobutyric acid (GABA)ergic and glutamatergic neurons due to aberrant induction of vesicular glutamate transporter 1 (vGlut1)-positive glutamatergic cells is responsible for impaired neuronal differentiation in the hippocampus following TBI. To elucidate the molecular mechanism, we found that TBI activates a transcription factor, Pax3, by increasing its acetylation status, and subsequently induces Ngn2 transcription. This event, in turn, augments the vGlut1-expressing glutamatergic neurons and accumulation of excess glutamate in the hippocampus that can affect neuronal differentiation. In our study the acetylation of Pax3 was increased due to loss of its interaction with a deacetylase, histone deacetylase 4 (HDAC4), which was downregulated after TBI. TBI-induced activation of GSK3β was responsible for the degradation of HDAC4. We also showed that overexpression of HDAC4 before TBI reduces Pax3 acetylation by restoring an interaction between HDAC4 and Pax3 in the hippocampus. This event prevents the aberrant induction of vGlut1-positive glutamatergic neurons by decreasing the Ngn2 level and subsequently reinforces the balance between GABAergic and glutamatergic neurons following TBI. Further, we found that overexpression of HDAC4 in the hippocampus improves anxiety, depressive-like behavior, and memory functions following TBI.
Collapse
Affiliation(s)
- Pampa Saha
- Department of Neurological Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Rajaneesh Gupta
- Department of Neurological Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Tanusree Sen
- Department of Neurological Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Nilkantha Sen
- Department of Neurological Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| |
Collapse
|
19
|
Hascup ER, Broderick SO, Russell MK, Fang Y, Bartke A, Boger HA, Hascup KN. Diet-induced insulin resistance elevates hippocampal glutamate as well as VGLUT1 and GFAP expression in AβPP/PS1 mice. J Neurochem 2019; 148:219-237. [PMID: 30472734 DOI: 10.1111/jnc.14634] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 10/31/2018] [Accepted: 11/13/2018] [Indexed: 12/21/2022]
Abstract
The symptomologies of Alzheimer's disease (AD) develop over decades suggesting modifiable lifestyle factors may contribute to disease pathogenesis. In humans, hyperinsulinemia associated with type 2 diabetes mellitus increases the risk for developing AD and both diseases share similar age-related etiologies including amyloidogenesis. Since we have demonstrated that soluble Aβ42 elicits glutamate release, we wanted to understand how diet-induced insulin resistance alters hippocampal glutamate dynamics, which are important for memory formation and consolidation. Eight to twelve-week-old C57BL/6J and AβPP/PS1 mice were placed on either a low-fat diet or high-fat diet (HFD) for 8 months. A HFD led to significant weight increases as well as impaired insulin sensitivity, glucose tolerance, and learning in both C57BL/6J and AβPP/PS1 mice. AβPP/PS1 low-fat diet mice had elevated hippocampal basal as well as stimulus-evoked glutamate release that was further increased with consumption of a HFD. Immunohistochemistry indicated an increase in vesicular glutamate transporter 1 and glial fibrillary acidic protein density in hippocampal subregions corresponding with this elevated extracellular glutamate. While no differences in hippocampal plaque load were observed, the elevated astrogliotic response surrounding the plaques in AβPP/PS1 HFD mice may have been a compensatory mechanism to control plaque accumulation. These data support that AβPP/PS1 mice have chronically elevated extracellular glutamate that is exacerbated by a HFD and that modifiable lifestyle factors such as obesity-induced insulin resistance can contribute to AD pathogenesis. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* and for *Open Data* because it made the data publicly available. The data can be accessed at https://osf.io/5whvu (figures for data) and https://osf.io/gd5vf (materials and methods). The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/. Cover Image for this issue: doi: 10.1111/jnc.14490.
Collapse
Affiliation(s)
- Erin R Hascup
- Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neurosciences Institute, Springfield, Illinois, USA.,Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, Illinois, USA
| | - Sarah O Broderick
- Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neurosciences Institute, Springfield, Illinois, USA
| | - Mary K Russell
- Department of Neuroscience, Center on Aging, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Yimin Fang
- Division of Geriatric Research, Department of Internal Medicine, Southern Illinois University School of Medicine, Springfield, Illinois, USA
| | - Andrzej Bartke
- Division of Geriatric Research, Department of Internal Medicine, Southern Illinois University School of Medicine, Springfield, Illinois, USA
| | - Heather A Boger
- Department of Neuroscience, Center on Aging, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Kevin N Hascup
- Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neurosciences Institute, Springfield, Illinois, USA
| |
Collapse
|
20
|
Affiliation(s)
- Kartik Venkatachalam
- Department of Integrative Biology and Pharmacology, McGovern Medical School at the University of Texas Health Science Center at Houston (UTHealth), Houston, TX, 77030, USA.,Programs in Cell and Regulatory Biology and Neuroscience at the Graduate School of Biomedical Sciences, University of Texas School of Medicine, Houston, TX, 77030, USA
| |
Collapse
|
21
|
Vernon SW, Goodchild J, Baines RA. The VAChTY49N mutation provides insecticide-resistance but perturbs evoked cholinergic neurotransmission in Drosophila. PLoS One 2018; 13:e0203852. [PMID: 30204788 PMCID: PMC6133381 DOI: 10.1371/journal.pone.0203852] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 08/28/2018] [Indexed: 12/05/2022] Open
Abstract
Global agriculture and the control of insect disease vectors have developed with a heavy reliance on insecticides. The increasing incidence of resistance, for virtually all insecticides, threatens both food supply and effective control of insect borne disease. CASPP ((5-chloro-1’-[(E)-3-(4-chlorophenyl)allyl]spiro[indoline-3,4’-piperidine]-1-yl}-(2-chloro-4-pyridyl)methanone)) compounds are a potential new class of neuroactive insecticide specifically targeting the Vesicular Acetylcholine Transporter (VAChT). Resistance to CASPP, under laboratory conditions, has been reported following either up-regulation of wildtype VAChT expression or the presence of a specific point mutation (VAChTY49N). However, the underlying mechanism of CASPP-resistance, together with the consequence to insect viability of achieving resistance, is unknown. In this study, we use electrophysiological characterisation of cholinergic release at Drosophila larval interneuron→motoneuron synapses to investigate the physiological implications of these two identified modes of CASPP resistance. We show that both VAChT up-regulation or the expression of VAChTY49N increases miniature (mini) release frequency. Mini frequency appears deterministic of CASPP activity. However, maintenance of SV release is not indicative of resistance in all cases. This is evidenced through expression of syntaxin or complexin mutants (sytx3-61/cpxSH1) that show similarly high mini release frequency but are not resistant to CASPP. The VAChTY49N mutation additionally disrupts action potential-evoked cholinergic release and fictive locomotor patterning through depletion of releasable synaptic vesicles. This observation suggests a functional trade-off for this point mutation, which is not seen when wildtype VAChT is up-regulated.
Collapse
Affiliation(s)
- Samuel W. Vernon
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Jim Goodchild
- Syngenta Crop Protection Research, Bracknell, Berkshire, United Kingdom
| | - Richard A. Baines
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
- * E-mail:
| |
Collapse
|
22
|
Steinkellner T, Zell V, Farino ZJ, Sonders MS, Villeneuve M, Freyberg RJ, Przedborski S, Lu W, Freyberg Z, Hnasko TS. Role for VGLUT2 in selective vulnerability of midbrain dopamine neurons. J Clin Invest 2018; 128:774-788. [PMID: 29337309 DOI: 10.1172/jci95795] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 11/21/2017] [Indexed: 12/22/2022] Open
Abstract
Parkinson's disease is characterized by the loss of dopamine (DA) neurons in the substantia nigra pars compacta (SNc). DA neurons in the ventral tegmental area are more resistant to this degeneration than those in the SNc, though the mechanisms for selective resistance or vulnerability remain poorly understood. A key to elucidating these processes may lie within the subset of DA neurons that corelease glutamate and express the vesicular glutamate transporter VGLUT2. Here, we addressed the potential relationship between VGLUT expression and DA neuronal vulnerability by overexpressing VGLUT in DA neurons of flies and mice. In Drosophila, VGLUT overexpression led to loss of select DA neuron populations. Similarly, expression of VGLUT2 specifically in murine SNc DA neurons led to neuronal loss and Parkinsonian behaviors. Other neuronal cell types showed no such sensitivity, suggesting that DA neurons are distinctively vulnerable to VGLUT2 expression. Additionally, most DA neurons expressed VGLUT2 during development, and coexpression of VGLUT2 with DA markers increased following injury in the adult. Finally, conditional deletion of VGLUT2 made DA neurons more susceptible to Parkinsonian neurotoxins. These data suggest that the balance of VGLUT2 expression is a crucial determinant of DA neuron survival. Ultimately, manipulation of this VGLUT2-dependent process may represent an avenue for therapeutic development.
Collapse
Affiliation(s)
| | - Vivien Zell
- Department of Neurosciences, UCSD, La Jolla, California, USA
| | - Zachary J Farino
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | | | - Michael Villeneuve
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Robin J Freyberg
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Serge Przedborski
- Department of Neurology, and.,Department of Pathology and Cell Biology, Columbia University, New York, New York, USA
| | - Wei Lu
- Synapse and Neural Circuit Research Unit, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Zachary Freyberg
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Thomas S Hnasko
- Department of Neurosciences, UCSD, La Jolla, California, USA
| |
Collapse
|
23
|
Ohgomori T, Yamasaki R, Kira JI, Jinno S. Upregulation of Vesicular Glutamate Transporter 2 and STAT3 Activation in the Spinal Cord of Mice Receiving 3,3'-Iminodipropionitrile. Neurotox Res 2017; 33:768-780. [PMID: 28965218 DOI: 10.1007/s12640-017-9822-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Revised: 09/14/2017] [Accepted: 09/20/2017] [Indexed: 12/12/2022]
Abstract
Chronic administration of 3,3'-iminodipropionitrile (IDPN) causes axonal impairment. Although controversy still remains, it has been suggested that IDPN intoxication mimics the axonopathy of amyotrophic lateral sclerosis (ALS). Interestingly, recent studies including our own showed that signal transducer and activator of transcription 3 (STAT3) in spinal α-motoneurons was activated in both IDPN-treated mice and SOD1 G93A mice, a genetic model of familial ALS. Because activation of STAT3 occurs in response to various stimuli, such as axonal injury, ischemia, and excessive glutamate, here we focused on a potential link between phosphorylated STAT3 (pSTAT3, an active form) and vesicular glutamate transporter 2 (VGluT2, a regulator of glutamate storage and release) in IDPN-treated mice and SOD1 G93A mice. Impairment of axonal transport was confirmed by western blot analysis: the expression levels of phosphorylated neurofilament H were elevated in both models. As shown in SOD1 G93A mice, the expression frequencies of VGluT2 in synaptophysin-positive (SYP)+ presynaptic terminals around spinal α-motoneurons were significantly higher in IDPN-treated mice than in vehicle controls. The coverages of spinal α-motoneurons by VGluT2+ presynaptic terminals were more elevated around pSTAT3+ cells than around pSTAT3- cells in IDPN-treated mice and SOD1 G93A mice. Considering that excessive glutamate is shown to be involved in axonal impairment and STAT3 activation, the present results suggest that IDPN-induced upregulation of VGluT2 may result in an increase in glutamate, which might cause axonopathy and induction of pSTAT3. The link between upregulation of VGluT2 and activation of STAT3 via glutamate may represent a common pathological feature of IDPN-treated mice and SOD1 G93A mice.
Collapse
Affiliation(s)
- Tomohiro Ohgomori
- Department of Anatomy and Neuroscience, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Ryo Yamasaki
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Jun-Ichi Kira
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Shozo Jinno
- Department of Anatomy and Neuroscience, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
| |
Collapse
|
24
|
Li J, Zhang YV, Asghari Adib E, Stanchev DT, Xiong X, Klinedinst S, Soppina P, Jahn TR, Hume RI, Rasse TM, Collins CA. Restraint of presynaptic protein levels by Wnd/DLK signaling mediates synaptic defects associated with the kinesin-3 motor Unc-104. eLife 2017; 6:e24271. [PMID: 28925357 PMCID: PMC5605197 DOI: 10.7554/elife.24271] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 08/11/2017] [Indexed: 12/19/2022] Open
Abstract
The kinesin-3 family member Unc-104/KIF1A is required for axonal transport of many presynaptic components to synapses, and mutation of this gene results in synaptic dysfunction in mice, flies and worms. Our studies at the Drosophila neuromuscular junction indicate that many synaptic defects in unc-104-null mutants are mediated independently of Unc-104's transport function, via the Wallenda (Wnd)/DLK MAP kinase axonal damage signaling pathway. Wnd signaling becomes activated when Unc-104's function is disrupted, and leads to impairment of synaptic structure and function by restraining the expression level of active zone (AZ) and synaptic vesicle (SV) components. This action concomitantly suppresses the buildup of synaptic proteins in neuronal cell bodies, hence may play an adaptive role to stresses that impair axonal transport. Wnd signaling also becomes activated when pre-synaptic proteins are over-expressed, suggesting the existence of a feedback circuit to match synaptic protein levels to the transport capacity of the axon.
Collapse
Affiliation(s)
- Jiaxing Li
- Department of Molecular, Cellular, and Developmental BiologyUniversity of MichiganAnn ArborUnited States
| | - Yao V Zhang
- Junior Research Group Synaptic PlasticityHertie-Institute for Clinical Brain Research, University of TübingenTübingenGermany
- Graduate School of Cellular and Molecular NeuroscienceUniversity of TübingenTübingenGermany
| | - Elham Asghari Adib
- Department of Molecular, Cellular, and Developmental BiologyUniversity of MichiganAnn ArborUnited States
| | - Doychin T Stanchev
- Junior Research Group Synaptic PlasticityHertie-Institute for Clinical Brain Research, University of TübingenTübingenGermany
- Graduate School of Cellular and Molecular NeuroscienceUniversity of TübingenTübingenGermany
| | - Xin Xiong
- Department of Molecular, Cellular, and Developmental BiologyUniversity of MichiganAnn ArborUnited States
| | - Susan Klinedinst
- Department of Molecular, Cellular, and Developmental BiologyUniversity of MichiganAnn ArborUnited States
| | - Pushpanjali Soppina
- Department of Molecular, Cellular, and Developmental BiologyUniversity of MichiganAnn ArborUnited States
| | - Thomas Robert Jahn
- CHS Research Group Proteostasis in Neurodegenerative DiseaseDKFZ Deutsches KrebsforschungszentrumHeidelbergGermany
| | - Richard I Hume
- Department of Molecular, Cellular, and Developmental BiologyUniversity of MichiganAnn ArborUnited States
| | - Tobias M Rasse
- Junior Research Group Synaptic PlasticityHertie-Institute for Clinical Brain Research, University of TübingenTübingenGermany
- CHS Research Group Proteostasis in Neurodegenerative DiseaseDKFZ Deutsches KrebsforschungszentrumHeidelbergGermany
| | - Catherine A Collins
- Department of Molecular, Cellular, and Developmental BiologyUniversity of MichiganAnn ArborUnited States
| |
Collapse
|
25
|
Ohgomori T, Yamasaki R, Takeuchi H, Kadomatsu K, Kira JI, Jinno S. Differential involvement of vesicular and glial glutamate transporters around spinal α-motoneurons in the pathogenesis of SOD1 G93A mouse model of amyotrophic lateral sclerosis. Neuroscience 2017; 356:114-124. [PMID: 28526579 DOI: 10.1016/j.neuroscience.2017.05.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/31/2017] [Accepted: 05/08/2017] [Indexed: 12/14/2022]
Abstract
From a view point of the glutamate excitotoxicity theory, several studies have suggested that abnormal glutamate homeostasis via dysfunction of glial glutamate transporter-1 (GLT-1) may underlie neurodegeneration in amyotrophic lateral sclerosis (ALS). However, the detailed role of GLT-1 in the pathogenies of ALS remains controversial. To assess this issue, here we elucidated structural alterations associated with dysregulation of glutamate homeostasis using SOD1G93A mice, a genetic model of familial ALS. We first examined the viability of α-motoneurons in the lumbar spinal cord of SOD1G93A mice. Measurement of the soma size and density indicated that α-motoneurons might be intact at 9weeks of age (presymptomatic stage), then soma shrinkage began at 15weeks of age (progressive stage), and finally neuronal density declined at 21weeks of age (end stage). Next, we carried out the line profile analysis, and found that the coverage of α-motoneurons by GLT-1-positive (GLT-1+) astrocytic processes was decreased only at 21weeks of age, while the reduction of coverage of α-motoneurons by synaptophysin-positive (SYP+) presynaptic terminals began at 15weeks of age. Interestingly, the coverage of α-motoneurons by VGluT2+ presynaptic terminals was transiently increased at 9weeks of age, and then gradually decreased towards 21weeks of age. On the other hand, there were no time-dependent alterations in the coverage of α-motoneurons by GABAergic presynaptic terminals. These findings suggest that VGluT2 and GLT-1 may be differentially involved in the pathogenesis of ALS via abnormal glutamate homeostasis at the presymptomatic stage and end stage of disease, respectively.
Collapse
Affiliation(s)
- Tomohiro Ohgomori
- Department of Anatomy and Neuroscience, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Ryo Yamasaki
- Department of Neurology, Neurological Institute, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Hideyuki Takeuchi
- Department of Neuroimmunology, Research Institute of Environmental Medicine, Nagoya University, Nagoya 464-8601, Japan; Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Kenji Kadomatsu
- Department of Biochemistry, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Jun-Ichi Kira
- Department of Neurology, Neurological Institute, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Shozo Jinno
- Department of Anatomy and Neuroscience, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582, Japan.
| |
Collapse
|
26
|
Characterization of a Human Point Mutation of VGLUT3 (p.A211V) in the Rodent Brain Suggests a Nonuniform Distribution of the Transporter in Synaptic Vesicles. J Neurosci 2017; 37:4181-4199. [PMID: 28314816 DOI: 10.1523/jneurosci.0282-16.2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Revised: 02/21/2017] [Accepted: 02/23/2017] [Indexed: 11/21/2022] Open
Abstract
The atypical vesicular glutamate transporter type 3 (VGLUT3) is expressed by subpopulations of neurons using acetylcholine, GABA, or serotonin as neurotransmitters. In addition, VGLUT3 is expressed in the inner hair cells of the auditory system. A mutation (p.A211V) in the gene that encodes VGLUT3 is responsible for progressive deafness in two unrelated families. In this study, we investigated the consequences of the p.A211V mutation in cell cultures and in the CNS of a mutant mouse. The mutation substantially decreased VGLUT3 expression (-70%). We measured VGLUT3-p.A211V activity by vesicular uptake in BON cells, electrophysiological recording of isolated neurons, and its ability to stimulate serotonergic accumulation in cortical synaptic vesicles. Despite a marked loss of expression, the activity of the mutated isoform was only minimally altered. Furthermore, mutant mice displayed none of the behavioral alterations that have previously been reported in VGLUT3 knock-out mice. Finally, we used stimulated emission depletion microscopy to analyze how the mutation altered VGLUT3 distribution within the terminals of mice expressing the mutated isoform. The mutation appeared to reduce the expression of the VGLUT3 transporter by simultaneously decreasing the number of VGLUT3-positive synaptic vesicles and the amount of VGLUT3 per synapses. These observations suggested that VGLUT3 global activity is not linearly correlated with VGLUT3 expression. Furthermore, our data unraveled a nonuniform distribution of VGLUT3 in synaptic vesicles. Identifying the mechanisms responsible for this complex vesicular sorting will be critical to understand VGLUT's involvement in normal and pathological conditions.SIGNIFICANCE STATEMENT VGLUT3 is an atypical member of the vesicular glutamate transporter family. A point mutation of VGLUT3 (VGLUT3-p.A211V) responsible for a progressive loss of hearing has been identified in humans. We observed that this mutation dramatically reduces VGLUT3 expression in terminals (∼70%) without altering its function. Furthermore, using stimulated emission depletion microscopy, we found that reducing the expression levels of VGLUT3 diminished the number of VGLUT3-positive vesicles at synapses. These unexpected findings challenge the vision of a uniform distribution of synaptic vesicles at synapses. Therefore, the overall activity of VGLUT3 is not proportional to the level of VGLUT3 expression. These data will be key in interpreting the role of VGLUTs in human pathologies.
Collapse
|
27
|
Rossano AJ, Kato A, Minard KI, Romero MF, Macleod GT. Na + /H + exchange via the Drosophila vesicular glutamate transporter mediates activity-induced acid efflux from presynaptic terminals. J Physiol 2016; 595:805-824. [PMID: 27641622 DOI: 10.1113/jp273105] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 09/14/2016] [Indexed: 01/26/2023] Open
Abstract
KEY POINTS Intracellular pH regulation is vital to neurons as nerve activity produces large and rapid acid loads in presynaptic terminals. Rapid clearance of acid loads is necessary to maintain control of neurotransmission, but neuronal acid clearance mechanisms remain poorly understood. Glutamate is loaded into synaptic vesicles via the vesicular glutamate transporter (VGLUT), a mechanism conserved across phyla, and this study reports a previously unknown role for VGLUT as an acid-extruding protein when deposited in the plasmamembrane during exocytosis. The finding was made in Drosophila (fruit fly) larval motor neurons through a combined pharamacological and genetic dissection of presynaptic pH homeostatic mechanisms. A dual role for VGLUT serves to integrate neuronal activity and pH regulation in presynaptic nerve terminals. ABSTRACT Neuronal activity can result in transient acidification of presynaptic terminals, and such shifts in cytosolic pH (pHcyto ) probably influence mechanisms underlying forms of synaptic plasticity with a presynaptic locus. As neuronal activity drives acid loading in presynaptic terminals, we hypothesized that the same activity might drive acid efflux mechanisms to maintain pHcyto homeostasis. To better understand the integration of neuronal activity and pHcyto regulation we investigated the acid extrusion mechanisms at Drosophila glutamatergic motorneuron terminals. Expression of a fluorescent genetically encoded pH indicator, named 'pHerry', in the presynaptic cytosol revealed acid efflux following nerve activity to be greater than that predicted from measurements of the intrinsic rate of acid efflux. Analysis of activity-induced acid transients in terminals deficient in either endocytosis or exocytosis revealed an acid efflux mechanism reliant upon synaptic vesicle exocytosis. Pharmacological and genetic dissection in situ and in a heterologous expression system indicate that this acid efflux is mediated by conventional plasmamembrane acid transporters, and also by previously unrecognized intrinsic H+ /Na+ exchange via the Drosophila vesicular glutamate transporter (DVGLUT). DVGLUT functions not only as a vesicular glutamate transporter but also serves as an acid-extruding protein when deposited on the plasmamembrane.
Collapse
Affiliation(s)
- Adam J Rossano
- School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - Akira Kato
- Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, 226-8503, Japan.,Physiology & Biomedical Engineering and Nephrology & Hypertension, Mayo Clinic College of Medicine, Rochester, MN, 55905, USA
| | - Karyl I Minard
- Biological Sciences & Wilkes Honors College, Florida Atlantic University, Jupiter, FL, 33431, USA
| | - Michael F Romero
- Physiology & Biomedical Engineering and Nephrology & Hypertension, Mayo Clinic College of Medicine, Rochester, MN, 55905, USA
| | - Gregory T Macleod
- Biological Sciences & Wilkes Honors College, Florida Atlantic University, Jupiter, FL, 33431, USA
| |
Collapse
|
28
|
Gadhave K, Bolshette N, Ahire A, Pardeshi R, Thakur K, Trandafir C, Istrate A, Ahmed S, Lahkar M, Muresanu DF, Balea M. The ubiquitin proteasomal system: a potential target for the management of Alzheimer's disease. J Cell Mol Med 2016; 20:1392-407. [PMID: 27028664 PMCID: PMC4929298 DOI: 10.1111/jcmm.12817] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 01/17/2016] [Indexed: 01/06/2023] Open
Abstract
The cellular quality control system degrades abnormal or misfolded proteins and consists of three different mechanisms: the ubiquitin proteasomal system (UPS), autophagy and molecular chaperones. Any disturbance in this system causes proteins to accumulate, resulting in neurodegenerative diseases such as amyotrophic lateral sclerosis, Alzheimer's disease (AD), Parkinson's disease, Huntington's disease and prion or polyglutamine diseases. Alzheimer's disease is currently one of the most common age-related neurodegenerative diseases. However, its exact cause and pathogenesis are unknown. Currently approved medications for AD provide symptomatic relief; however, they fail to influence disease progression. Moreover, the components of the cellular quality control system represent an important focus for the development of targeted and potent therapies for managing AD. This review aims to evaluate whether existing evidence supports the hypothesis that UPS impairment causes the early pathogenesis of neurodegenerative disorders. The first part presents basic information about the UPS and its molecular components. The next part explains how the UPS is involved in neurodegenerative disorders. Finally, we emphasize how the UPS influences the management of AD. This review may help in the design of future UPS-related therapies for AD.
Collapse
Affiliation(s)
- Kundlik Gadhave
- Laboratory of Neurobiology, Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati, Assam, India
| | - Nityanand Bolshette
- Institutional Level Biotech hub (IBT hub), Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati, Assam, India
| | - Ashutosh Ahire
- Laboratory of Neurobiology, Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati, Assam, India
| | - Rohit Pardeshi
- Institutional Level Biotech hub (IBT hub), Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati, Assam, India
| | - Krishan Thakur
- Institutional Level Biotech hub (IBT hub), Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati, Assam, India
| | - Cristiana Trandafir
- Faculty of Medicine, University of Medicine and Pharmacy "Iuliu Hatieganu", Cluj-Napoca, Romania
| | - Alexandru Istrate
- Faculty of Medicine, University of Medicine and Pharmacy "Iuliu Hatieganu", Cluj-Napoca, Romania
| | - Sahabuddin Ahmed
- Laboratory of Neurobiology, Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati, Assam, India
| | - Mangala Lahkar
- Laboratory of Neurobiology, Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati, Assam, India
- Institutional Level Biotech hub (IBT hub), Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati, Assam, India
| | - Dafin F Muresanu
- Faculty of Medicine, University of Medicine and Pharmacy "Iuliu Hatieganu", Cluj-Napoca, Romania
- Department of Clinical Neurosciences, University of Medicine and Pharmacy "Iuliu Hatieganu", Cluj-Napoca, Romania
- "RoNeuro" Institute for Neurological Research and Diagnostic, Cluj-Napoca, Romania
| | - Maria Balea
- Department of Clinical Neurosciences, University of Medicine and Pharmacy "Iuliu Hatieganu", Cluj-Napoca, Romania
| |
Collapse
|
29
|
Pani G, Verslegers M, Quintens R, Samari N, de Saint-Georges L, van Oostveldt P, Baatout S, Benotmane MA. Combined Exposure to Simulated Microgravity and Acute or Chronic Radiation Reduces Neuronal Network Integrity and Survival. PLoS One 2016; 11:e0155260. [PMID: 27203085 PMCID: PMC4874625 DOI: 10.1371/journal.pone.0155260] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 04/26/2016] [Indexed: 12/21/2022] Open
Abstract
During orbital or interplanetary space flights, astronauts are exposed to cosmic radiations and microgravity. However, most earth-based studies on the potential health risks of space conditions have investigated the effects of these two conditions separately. This study aimed at assessing the combined effect of radiation exposure and microgravity on neuronal morphology and survival in vitro. In particular, we investigated the effects of simulated microgravity after acute (X-rays) or during chronic (Californium-252) exposure to ionizing radiation using mouse mature neuron cultures. Acute exposure to low (0.1 Gy) doses of X-rays caused a delay in neurite outgrowth and a reduction in soma size, while only the high dose impaired neuronal survival. Of interest, the strongest effect on neuronal morphology and survival was evident in cells exposed to microgravity and in particular in cells exposed to both microgravity and radiation. Removal of neurons from simulated microgravity for a period of 24 h was not sufficient to recover neurite length, whereas the soma size showed a clear re-adaptation to normal ground conditions. Genome-wide gene expression analysis confirmed a modulation of genes involved in neurite extension, cell survival and synaptic communication, suggesting that these changes might be responsible for the observed morphological effects. In general, the observed synergistic changes in neuronal network integrity and cell survival induced by simulated space conditions might help to better evaluate the astronaut's health risks and underline the importance of investigating the central nervous system and long-term cognition during and after a space flight.
Collapse
Affiliation(s)
- Giuseppe Pani
- Radiobiology Unit, Laboratory of Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre, SCK•CEN, Mol, Belgium
- Cell Systems and Imaging Research Group (CSI), Department of Molecular Biotechnology, Ghent University, Ghent, Belgium
- Laboratory of Membrane Biochemistry and Applied Nutrition, Department of Pharmacology and Bio-molecular Sciences (DiSFeB), Università degli Studi di Milano, Milano, Italy
| | - Mieke Verslegers
- Radiobiology Unit, Laboratory of Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre, SCK•CEN, Mol, Belgium
| | - Roel Quintens
- Radiobiology Unit, Laboratory of Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre, SCK•CEN, Mol, Belgium
| | - Nada Samari
- Radiobiology Unit, Laboratory of Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre, SCK•CEN, Mol, Belgium
| | - Louis de Saint-Georges
- Radiobiology Unit, Laboratory of Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre, SCK•CEN, Mol, Belgium
| | - Patrick van Oostveldt
- Cell Systems and Imaging Research Group (CSI), Department of Molecular Biotechnology, Ghent University, Ghent, Belgium
| | - Sarah Baatout
- Radiobiology Unit, Laboratory of Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre, SCK•CEN, Mol, Belgium
- Cell Systems and Imaging Research Group (CSI), Department of Molecular Biotechnology, Ghent University, Ghent, Belgium
| | - Mohammed Abderrafi Benotmane
- Radiobiology Unit, Laboratory of Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre, SCK•CEN, Mol, Belgium
- * E-mail:
| |
Collapse
|
30
|
Cao Y, Gou Z, Du Y, Fan Y, Liang L, Yan Y, Lin P, Jin M, Du Y. Glutamatergic and central cholinergic dysfunction in the CA1, CA2 and CA3 fields on spatial learning and memory in chronic cerebral ischemia-Induced vascular dementia of rats. Neurosci Lett 2016; 620:169-76. [PMID: 27040427 DOI: 10.1016/j.neulet.2016.03.039] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 02/25/2016] [Accepted: 03/23/2016] [Indexed: 10/22/2022]
Abstract
Chronic cerebral ischemia (CCI) is associated with cognitive decline in aging, vascular dementia and Alzheimer's disease. Substantial evidence has shown that chronic cerebral ischemia may cause cognitive impairment, but the underlying neurobiological mechanism is poorly understood so far. In the present study, we used a rat model of chronic cerebral ischemia by permanent bilateral common carotid artery occlusion (BCCAO) to investigate the alterations of glutamatergic and central cholinergic dysfunction, and their causal relationship with the cognitive deficits induced by chronic cerebral ischemia. We found that BCCAO rats exhibited spatial learning and memory impairments dysfunction 3 month after BCCAO. Meanwhile, vGluT levels as well as glutamatergic and central cholinergic positive neurons in the hippocampus CA1-3 field significantly decreased. The protection of glutamergic and cholinergic neurons or regulating glutamate and central cholinergic levels in hippocampal subregion may have beneficial effects on cognitive impairments associated with the possible mechanism in CCI-induced vascular dementia.
Collapse
Affiliation(s)
- Yanjing Cao
- Department of Neurology, Hangzhou Third Hospital, 38 xihu Road, Hangzhou 310009, PR China
| | - Zengmei Gou
- Weifang Second People's Hospital, 7 Yuanxiao Street, WeiFang, Shandong 261041, PR China
| | - Yifeng Du
- Department of Neurology, Shandong Provincial Hospital, Shandong University, 44 Wenhua xi Road, Jinan 2500013, PR China.
| | - Yongjun Fan
- Eskitis institute for drug discovery, Griffith University, QLD 4111, Australia
| | - Lizhen Liang
- Department of Neurology, Hangzhou Third Hospital, 38 xihu Road, Hangzhou 310009, PR China
| | - Yongxing Yan
- Department of Neurology, Hangzhou Third Hospital, 38 xihu Road, Hangzhou 310009, PR China
| | - Ping Lin
- Department of Neurology, Hangzhou Third Hospital, 38 xihu Road, Hangzhou 310009, PR China
| | - Mudan Jin
- Department of Neurology, Hangzhou Third Hospital, 38 xihu Road, Hangzhou 310009, PR China
| | - Yifenf Du
- Department of Neurology, Shandong Provincial Hospital, Shandong University, 44 Wenhua xi Road, Jinan 2500013, PR China
| |
Collapse
|
31
|
Kim YS, Kim TH, McKemy DD, Bae YC. Expression of vesicular glutamate transporters in transient receptor potential melastatin 8 (TRPM8)-positive dental afferents in the mouse. Neuroscience 2015; 303:378-88. [PMID: 26166724 DOI: 10.1016/j.neuroscience.2015.07.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 07/01/2015] [Accepted: 07/02/2015] [Indexed: 01/31/2023]
Abstract
Transient receptor potential melastatin 8 (TRPM8) is activated by innocuous cool and noxious cold and plays a crucial role in cold-induced acute pain and pain hypersensitivity. To help understand the mechanism of TRPM8-mediated cold perception under normal and pathologic conditions, we used light microscopic immunohistochemistry and Western blot analysis in mice expressing a genetically encoded axonal tracer in TRPM8-positive (+) neurons. We investigated the coexpression of TRPM8 and vesicular glutamate transporter 1 (VGLUT1) and VGLUT2 in the trigeminal ganglion (TG) and the dental pulp before and after inducing pulpal inflammation. Many TRPM8+ neurons in the TG and axons in the dental pulp expressed VGLUT2, while none expressed VGLUT1. TRPM8+ axons were dense in the pulp horn and peripheral pulp and also frequently observed in the dentinal tubules. Following pulpal inflammation, the proportion of VGLUT2+ and of VGLUT2+/TRPM8+ neurons increased significantly, whereas that of TRPM8+ neurons remained unchanged. Our findings suggest the existence of VGLUT2 (but not VGLUT1)-mediated glutamate signaling in TRPM8+ neurons possibly underlying the cold-induced acute pain and hypersensitivity to cold following pulpal inflammation.
Collapse
Affiliation(s)
- Y S Kim
- Department of Anatomy and Neurobiology, School of Dentistry, Kyungpook National University, Daegu 700-412, South Korea
| | - T H Kim
- Department of Anatomy and Neurobiology, School of Dentistry, Kyungpook National University, Daegu 700-412, South Korea
| | - D D McKemy
- Neurobiology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Y C Bae
- Department of Anatomy and Neurobiology, School of Dentistry, Kyungpook National University, Daegu 700-412, South Korea.
| |
Collapse
|
32
|
Lin L, Yee SW, Kim RB, Giacomini KM. SLC transporters as therapeutic targets: emerging opportunities. Nat Rev Drug Discov 2015; 14:543-60. [PMID: 26111766 DOI: 10.1038/nrd4626] [Citation(s) in RCA: 510] [Impact Index Per Article: 56.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Solute carrier (SLC) transporters - a family of more than 300 membrane-bound proteins that facilitate the transport of a wide array of substrates across biological membranes - have important roles in physiological processes ranging from the cellular uptake of nutrients to the absorption of drugs and other xenobiotics. Several classes of marketed drugs target well-known SLC transporters, such as neurotransmitter transporters, and human genetic studies have provided powerful insight into the roles of more-recently characterized SLC transporters in both rare and common diseases, indicating a wealth of new therapeutic opportunities. This Review summarizes knowledge on the roles of SLC transporters in human disease, describes strategies to target such transporters, and highlights current and investigational drugs that modulate SLC transporters, as well as promising drug targets.
Collapse
Affiliation(s)
- Lawrence Lin
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, California 94158, USA
| | - Sook Wah Yee
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, California 94158, USA
| | - Richard B Kim
- Division of Clinical Pharmacology, Department of Medicine, University of Western Ontario, London Health Science Centre, London, Ontario N6A 5A5, Canada
| | - Kathleen M Giacomini
- 1] Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, California 94158, USA. [2] Institute for Human Genetics, University of California San Francisco, San Francisco, California 94158, USA
| |
Collapse
|
33
|
Verma P, Augustine GJ, Ammar MR, Tashiro A, Cohen SM. A neuroprotective role for microRNA miR-1000 mediated by limiting glutamate excitotoxicity. Nat Neurosci 2015; 18:379-85. [PMID: 25643297 DOI: 10.1038/nn.3935] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 01/06/2015] [Indexed: 12/17/2022]
Abstract
Evidence has begun to emerge for microRNAs as regulators of synaptic signaling, specifically acting to control postsynaptic responsiveness during synaptic transmission. In this report, we provide evidence that Drosophila melanogaster miR-1000 acts presynaptically to regulate glutamate release at the synapse by controlling expression of the vesicular glutamate transporter (VGlut). Genetic deletion of miR-1000 led to elevated apoptosis in the brain as a result of glutamatergic excitotoxicity. The seed-similar miR-137 regulated VGluT2 expression in mouse neurons. These conserved miRNAs share a neuroprotective function in the brains of flies and mice. Drosophila miR-1000 showed activity-dependent expression, which might serve as a mechanism to allow neuronal activity to fine-tune the strength of excitatory synaptic transmission.
Collapse
Affiliation(s)
- Pushpa Verma
- 1] Institute of Molecular and Cell Biology, Singapore. [2] Department of Biological Sciences, National University of Singapore, Singapore
| | - George J Augustine
- 1] Institute of Molecular and Cell Biology, Singapore. [2] Duke-NUS Graduate Medical School, Singapore. [3] Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul, Republic of Korea. [4] Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Mohamed-Raafet Ammar
- 1] Warwick-Nanyang Technological University Neuroscience Programme, School of Biological Sciences, Nanyang Technological University, Singapore. [2] School of Life Sciences, University of Warwick, Coventry, UK
| | - Ayumu Tashiro
- 1] Warwick-Nanyang Technological University Neuroscience Programme, School of Biological Sciences, Nanyang Technological University, Singapore. [2] School of Life Sciences, University of Warwick, Coventry, UK
| | - Stephen M Cohen
- 1] Institute of Molecular and Cell Biology, Singapore. [2] Department of Biological Sciences, National University of Singapore, Singapore
| |
Collapse
|
34
|
Hunsberger HC, Rudy CC, Batten SR, Gerhardt GA, Reed MN. P301L tau expression affects glutamate release and clearance in the hippocampal trisynaptic pathway. J Neurochem 2015; 132:169-82. [PMID: 25319522 PMCID: PMC4302046 DOI: 10.1111/jnc.12967] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 09/25/2014] [Accepted: 10/02/2014] [Indexed: 12/31/2022]
Abstract
Individuals at risk of developing Alzheimer's disease (AD) often exhibit hippocampal hyperexcitability. A growing body of evidence suggests that perturbations in the glutamatergic tripartite synapse may underlie this hyperexcitability. Here, we used a tau mouse model of AD (rTg(TauP301L)4510) to examine the effects of tau pathology on hippocampal glutamate regulation. We found a 40% increase in hippocampal vesicular glutamate transporter, which packages glutamate into vesicles, and has previously been shown to influence glutamate release, and a 40% decrease in hippocampal glutamate transporter 1, the major glutamate transporter responsible for removing glutamate from the extracellular space. To determine whether these alterations affected glutamate regulation in vivo, we measured tonic glutamate levels, potassium-evoked glutamate release, and glutamate uptake/clearance in the dentate gyrus, cornu ammonis 3(CA3), and cornu ammonis 1(CA1) regions of the hippocampus. P301L tau expression resulted in a 4- and 7-fold increase in potassium-evoked glutamate release in the dentate gyrus and CA3, respectively, and significantly decreased glutamate clearance in all three regions. Both release and clearance correlated with memory performance in the hippocampal-dependent Barnes maze task. Alterations in mice expressing P301L were observed at a time when tau pathology was subtle and before readily detectable neuron loss. These data suggest novel mechanisms by which tau may mediate hyperexcitability. Pre-synaptic vesicular glutamate transporters (vGLUTs) package glutamate into vesicles before exocytosis into the synaptic cleft. Once in the extracellular space, glutamate acts on glutamate receptors. Glutamate is removed from the extracellular space by excitatory amino acid transporters, including GLT-1, predominantly localized to glia. P301L tau expression increases vGLUT expression and glutamate release, while also decreasing GLT-1 expression and glutamate clearance.
Collapse
Affiliation(s)
- Holly C. Hunsberger
- Behavioral Neuroscience, Department of Psychology, University of Kentucky Health Sciences Center, Lexington, KY 40536-0298
| | - Carolyn C. Rudy
- Behavioral Neuroscience, Department of Psychology, University of Kentucky Health Sciences Center, Lexington, KY 40536-0298
| | - Seth R. Batten
- Center for Microelectrode Technology (CenMeT), Department of Anatomy and Neurobiology, University of Kentucky Health Sciences Center, Lexington, KY 40536-0298
| | - Greg A. Gerhardt
- Center for Microelectrode Technology (CenMeT), Department of Anatomy and Neurobiology, University of Kentucky Health Sciences Center, Lexington, KY 40536-0298
| | - Miranda N. Reed
- Behavioral Neuroscience, Department of Psychology, University of Kentucky Health Sciences Center, Lexington, KY 40536-0298
- Center for Neuroscience, West Virginia University, Morgantown, 26506 WV, USA
- Center for Basic and Translational Stroke Research, West Virginia University, Morgantown, 26506 WV, USA
| |
Collapse
|
35
|
Guindon J, Lin JS. Inflammatory pain models with capsaicin or glutamate injections: Are they comparable and reproducible? Clin Exp Pharmacol Physiol 2014; 41:947-9. [DOI: 10.1111/1440-1681.12306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Josée Guindon
- Department of Pharmacology and Neuroscience; Texas Tech University Health Sciences Center; Lubbock TX USA
| | - Jian-Sheng Lin
- Integrative Physiology of the Brain Arousal Systems; Lyon Neuroscience Research Center; INSERM U1028-CNRS UMR5292; Claude Bernard University; Lyon France
| |
Collapse
|
36
|
Cassar M, Issa AR, Riemensperger T, Petitgas C, Rival T, Coulom H, Iché-Torres M, Han KA, Birman S. A dopamine receptor contributes to paraquat-induced neurotoxicity in Drosophila. Hum Mol Genet 2014; 24:197-212. [PMID: 25158689 DOI: 10.1093/hmg/ddu430] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Long-term exposure to environmental oxidative stressors, like the herbicide paraquat (PQ), has been linked to the development of Parkinson's disease (PD), the most frequent neurodegenerative movement disorder. Paraquat is thus frequently used in the fruit fly Drosophila melanogaster and other animal models to study PD and the degeneration of dopaminergic neurons (DNs) that characterizes this disease. Here, we show that a D1-like dopamine (DA) receptor, DAMB, actively contributes to the fast central nervous system (CNS) failure induced by PQ in the fly. First, we found that a long-term increase in neuronal DA synthesis reduced DAMB expression and protected against PQ neurotoxicity. Secondly, a striking age-related decrease in PQ resistance in young adult flies correlated with an augmentation of DAMB expression. This aging-associated increase in oxidative stress vulnerability was not observed in a DAMB-deficient mutant. Thirdly, targeted inactivation of this receptor in glutamatergic neurons (GNs) markedly enhanced the survival of Drosophila exposed to either PQ or neurotoxic levels of DA, whereas, conversely, DAMB overexpression in these cells made the flies more vulnerable to both compounds. Fourthly, a mutation in the Drosophila ryanodine receptor (RyR), which inhibits activity-induced increase in cytosolic Ca(2+), also strongly enhanced PQ resistance. Finally, we found that DAMB overexpression in specific neuronal populations arrested development of the fly and that in vivo stimulation of either DNs or GNs increased PQ susceptibility. This suggests a model for DA receptor-mediated potentiation of PQ-induced neurotoxicity. Further studies of DAMB signaling in Drosophila could have implications for better understanding DA-related neurodegenerative disorders in humans.
Collapse
Affiliation(s)
- Marlène Cassar
- Genes Circuits Rhythms and Neuropathologies, Brain Plasticity Unit, CNRS, PSL Research University, ESPCI ParisTech, 10 rue Vauquelin, 75005 Paris, France
| | - Abdul-Raouf Issa
- Genes Circuits Rhythms and Neuropathologies, Brain Plasticity Unit, CNRS, PSL Research University, ESPCI ParisTech, 10 rue Vauquelin, 75005 Paris, France
| | - Thomas Riemensperger
- Genes Circuits Rhythms and Neuropathologies, Brain Plasticity Unit, CNRS, PSL Research University, ESPCI ParisTech, 10 rue Vauquelin, 75005 Paris, France
| | - Céline Petitgas
- Genes Circuits Rhythms and Neuropathologies, Brain Plasticity Unit, CNRS, PSL Research University, ESPCI ParisTech, 10 rue Vauquelin, 75005 Paris, France
| | - Thomas Rival
- Genetics and Physiopathology of Neurotransmission, Developmental Biology Institute of Marseille-Luminy, CNRS, Université de la Méditerranée, 13009 Marseille, France and
| | - Hélène Coulom
- Genetics and Physiopathology of Neurotransmission, Developmental Biology Institute of Marseille-Luminy, CNRS, Université de la Méditerranée, 13009 Marseille, France and
| | - Magali Iché-Torres
- Genetics and Physiopathology of Neurotransmission, Developmental Biology Institute of Marseille-Luminy, CNRS, Université de la Méditerranée, 13009 Marseille, France and
| | - Kyung-An Han
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX 79968, USA
| | - Serge Birman
- Genes Circuits Rhythms and Neuropathologies, Brain Plasticity Unit, CNRS, PSL Research University, ESPCI ParisTech, 10 rue Vauquelin, 75005 Paris, France Genetics and Physiopathology of Neurotransmission, Developmental Biology Institute of Marseille-Luminy, CNRS, Université de la Méditerranée, 13009 Marseille, France and
| |
Collapse
|
37
|
Wilson WW, Onyenwe W, Bradner JM, Nennig SE, Caudle WM. Developmental exposure to the organochlorine insecticide endosulfan alters expression of proteins associated with neurotransmission in the frontal cortex. Synapse 2014; 68:485-97. [PMID: 25042905 DOI: 10.1002/syn.21764] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 06/11/2014] [Indexed: 11/11/2022]
Abstract
Exposure to environmental contaminants, such as organochlorine insecticides during critical periods of neurodevelopment has been shown to be a major contributor to several neuropsychological deficits seen in children, adolescence, and adults. Although the neurobehavioral outcomes resulting from exposure to these compounds are known the neurotransmitter circuitry and molecular targets that mediate these endpoints have not been identified. Given the importance of the frontal cortex in facilitating numerous neuropsychological processes, our current study sought to investigate the effects of developmental exposure to the organochlorine insecticide, endosulfan, on the expression of specific proteins associated with neurotransmission in the frontal cortex. Utilizing in vitro models we were able to show endosulfan reduces cell viability in IMR-32 neuroblastoma cells in addition to reducing synaptic puncta and neurite outgrowth in primary cultured neurons isolated from the frontal cortex of mice. Elaborating these findings to an in vivo model we found that developmental exposure of female mice to endosulfan during gestation and lactation elicited significant alterations to the GABAergic (GAT1, vGAT, GABAA receptor), glutamatergic (vGlut and GluN2B receptor), and dopaminergic (DAT, TH, VMAT2, and D2 receptor) neurotransmitter systems in the frontal cortex of male offspring. These findings identify damage to critical neurotransmitter circuits and proteins in the frontal cortex, which may underlie the neurobehavioral deficits observed following developmental exposure to endosulfan and other organochlorine insecticides.
Collapse
Affiliation(s)
- W Wyatt Wilson
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, 30322-3090
| | | | | | | | | |
Collapse
|
38
|
Hunsberger HC, Rudy CC, Weitzner DS, Zhang C, Tosto DE, Knowlan K, Xu Y, Reed MN. Effect size of memory deficits in mice with adult-onset P301L tau expression. Behav Brain Res 2014; 272:181-95. [PMID: 25004446 DOI: 10.1016/j.bbr.2014.06.057] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 06/24/2014] [Accepted: 06/28/2014] [Indexed: 11/29/2022]
Abstract
Transgenic mice expressing mutations in tau have yielded essential discoveries for Alzheimer's disease. One of the most commonly used tau mouse models is the tet-off Tg(tauP301L)4510 model that expresses P301L human tau driven by the calcium-calmodulin kinase IIα (CaMKIIα) promoter system. Tau expression in this model is regulatable, allowing for suppression of mutant tau expression until adulthood and prevention of possible developmental alterations resulting from P301L tau expression during development. Here, we compared the effect and sample sizes needed for three learning and memory tasks in mice with adult-onset P301L tau expression. Our findings indicate that the Incremental Repeated Acquisition (IRA) and trace fear conditioning tasks, neither of which have previously been published with these mice, were highly sensitive to P301L tau expression, whereas the Morris water maze, the most commonly used task with this model, was the least sensitive. Memory deficits were observed at a time when tau pathology was subtle and prior to readily detectable neuronal loss. Thus, we provide essential information (effect and sample sizes needed) for establishing experimental designs at a time point when memory deficits are likely to go undetected if inadequate sample sizes are used. Our work also suggests the tet-off Tg4510 model provides a way to avoid mutant tau expression during the perinatal and early postnatal stages, thereby preventing possible developmental alterations unrelated to Alzheimer's disease.
Collapse
Affiliation(s)
- Holly C Hunsberger
- Department of Psychology, Behavioral Neuroscience, West Virginia University, Morgantown, WV 26506, USA
| | - Carolyn C Rudy
- Department of Psychology, Behavioral Neuroscience, West Virginia University, Morgantown, WV 26506, USA
| | - Daniel S Weitzner
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14214, USA
| | - Chong Zhang
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14214, USA
| | - David E Tosto
- Department of Psychology, Behavioral Neuroscience, West Virginia University, Morgantown, WV 26506, USA
| | - Kevin Knowlan
- Department of Psychology, Behavioral Neuroscience, West Virginia University, Morgantown, WV 26506, USA
| | - Ying Xu
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14214, USA
| | - Miranda N Reed
- Department of Psychology, Behavioral Neuroscience, West Virginia University, Morgantown, WV 26506, USA; Center for Neuroscience, West Virginia University, Morgantown, WV 26506, USA; Center for Basic and Translational Stroke Research, West Virginia University, Morgantown, WV 26506, USA; Department of Neurology, University of Minnesota, Minneapolis, MN 55455, USA; N. Bud Grossman Center for Memory Research and Care, University of Minnesota, Minneapolis, MN 55455, USA.
| |
Collapse
|
39
|
Drosophila melanogaster as a genetic model system to study neurotransmitter transporters. Neurochem Int 2014; 73:71-88. [PMID: 24704795 DOI: 10.1016/j.neuint.2014.03.015] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 03/20/2014] [Accepted: 03/24/2014] [Indexed: 12/30/2022]
Abstract
The model genetic organism Drosophila melanogaster, commonly known as the fruit fly, uses many of the same neurotransmitters as mammals and very similar mechanisms of neurotransmitter storage, release and recycling. This system offers a variety of powerful molecular-genetic methods for the study of transporters, many of which would be difficult in mammalian models. We review here progress made using Drosophila to understand the function and regulation of neurotransmitter transporters and discuss future directions for its use.
Collapse
|
40
|
Machamer JB, Collins SE, Lloyd TE. The ALS gene FUS regulates synaptic transmission at the Drosophila neuromuscular junction. Hum Mol Genet 2014; 23:3810-22. [PMID: 24569165 DOI: 10.1093/hmg/ddu094] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Mutations in the RNA binding protein Fused in sarcoma (FUS) are estimated to account for 5-10% of all inherited cases of amyotrophic lateral sclerosis (ALS), but the function of FUS in motor neurons is poorly understood. Here, we investigate the early functional consequences of overexpressing wild-type or ALS-associated mutant FUS proteins in Drosophila motor neurons, and compare them to phenotypes arising from loss of the Drosophila homolog of FUS, Cabeza (Caz). We find that lethality and locomotor phenotypes correlate with levels of FUS transgene expression, indicating that toxicity in developing motor neurons is largely independent of ALS-linked mutations. At the neuromuscular junction (NMJ), overexpression of either wild-type or mutant FUS results in decreased number of presynaptic active zones and altered postsynaptic glutamate receptor subunit composition, coinciding with a reduction in synaptic transmission as a result of both reduced quantal size and quantal content. Interestingly, expression of human FUS downregulates endogenous Caz levels, demonstrating that FUS autoregulation occurs in motor neurons in vivo. However, loss of Caz from motor neurons increases synaptic transmission as a result of increased quantal size, suggesting that the loss of Caz in animals expressing FUS does not contribute to motor deficits. These data demonstrate that FUS/Caz regulates NMJ development and plays an evolutionarily conserved role in modulating the strength of synaptic transmission in motor neurons.
Collapse
Affiliation(s)
| | | | - Thomas E Lloyd
- Department of Neurology, and The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| |
Collapse
|
41
|
Yang X, Liu Y, Liu C, Xie W, Huang E, Huang W, Wang J, Chen L, Wang H, Qiu P, Xu J, Zhang F, Wang H. Inhibition of ROCK2 expression protects against methamphetamine-induced neurotoxicity in PC12 cells. Brain Res 2013; 1533:16-25. [DOI: 10.1016/j.brainres.2013.08.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Revised: 07/17/2013] [Accepted: 08/03/2013] [Indexed: 10/26/2022]
|
42
|
Malet M, Vieytes CA, Lundgren KH, Seal RP, Tomasella E, Seroogy KB, Hökfelt T, Gebhart GF, Brumovsky PR. Transcript expression of vesicular glutamate transporters in lumbar dorsal root ganglia and the spinal cord of mice - effects of peripheral axotomy or hindpaw inflammation. Neuroscience 2013; 248:95-111. [PMID: 23727452 PMCID: PMC3800240 DOI: 10.1016/j.neuroscience.2013.05.044] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 05/22/2013] [Accepted: 05/22/2013] [Indexed: 11/30/2022]
Abstract
Using specific riboprobes, we characterized the expression of vesicular glutamate transporter (VGLUT)₁-VGLUT₃ transcripts in lumbar 4-5 (L4-5) dorsal root ganglions (DRGs) and the thoracolumbar to lumbosacral spinal cord in male BALB/c mice after a 1- or 3-day hindpaw inflammation, or a 7-day sciatic nerve axotomy. Sham animals were also included. In sham and contralateral L4-5 DRGs of injured mice, VGLUT₁-, VGLUT₂- and VGLUT₃ mRNAs were expressed in ∼45%, ∼69% or ∼17% of neuron profiles (NPs), respectively. VGLUT₁ was expressed in large and medium-sized NPs, VGLUT₂ in NPs of all sizes, and VGLUT₃ in small and medium-sized NPs. In the spinal cord, VGLUT₁ was restricted to a number of NPs at thoracolumbar and lumbar segments, in what appears to be the dorsal nucleus of Clarke, and in mid laminae III-IV. In contrast, VGLUT₂ was present in numerous NPs at all analyzed spinal segments, except the lateral aspects of the ventral horns, especially at the lumbar enlargement, where it was virtually absent. VGLUT₃ was detected in a discrete number of NPs in laminae III-IV of the dorsal horn. Axotomy resulted in a moderate decrease in the number of DRG NPs expressing VGLUT₃, whereas VGLUT₁ and VGLUT₂ were unaffected. Likewise, the percentage of NPs expressing VGLUT transcripts remained unaltered after hindpaw inflammation, both in DRGs and the spinal cord. Altogether, these results confirm previous descriptions on VGLUTs expression in adult mice DRGs, with the exception of VGLUT₁, whose protein expression was detected in a lower percentage of mouse DRG NPs. A detailed account on the location of neurons expressing VGLUTs transcripts in the adult mouse spinal cord is also presented. Finally, the lack of change in the number of neurons expressing VGLUT₁ and VGLUT₂ transcripts after axotomy, as compared to data on protein expression, suggests translational rather than transcriptional regulation of VGLUTs after injury.
Collapse
Affiliation(s)
- M Malet
- Faculty of Biomedical Sciences, Austral University, Buenos Aires, Argentina; CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas), Buenos Aires, Argentina
| | - C A Vieytes
- Faculty of Biomedical Sciences, Austral University, Buenos Aires, Argentina
| | - K H Lundgren
- Department of Neurology, University of Cincinnati, Cincinnati, OH, USA
| | - R P Seal
- Pittsburgh Center for Pain Research, Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - E Tomasella
- Faculty of Biomedical Sciences, Austral University, Buenos Aires, Argentina; CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas), Buenos Aires, Argentina
| | - K B Seroogy
- Department of Neurology, University of Cincinnati, Cincinnati, OH, USA
| | - T Hökfelt
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - G F Gebhart
- Pittsburgh Center for Pain Research, Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - P R Brumovsky
- Faculty of Biomedical Sciences, Austral University, Buenos Aires, Argentina; CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas), Buenos Aires, Argentina; Pittsburgh Center for Pain Research, Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA.
| |
Collapse
|
43
|
Azami Tameh A, Clarner T, Beyer C, Atlasi MA, Hassanzadeh G, Naderian H. Regional regulation of glutamate signaling during cuprizone-induced demyelination in the brain. Ann Anat 2013; 195:415-23. [PMID: 23711509 DOI: 10.1016/j.aanat.2013.03.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Revised: 02/25/2013] [Accepted: 03/18/2013] [Indexed: 12/14/2022]
Abstract
Glutamate excitotoxicity is associated with a wide range of neurodegenerative disorders and also seems to be involved in the pathology of demyelinating disorders such as multiple sclerosis (MS). Cuprizone-induced toxic demyelination shows clear characteristics of MS such as demyelination and axonal damage without the involvement of the innate immune system. In this study, we have evaluated glutamate signaling during cuprizone-induced demyelination in the white and gray matter of mouse brain by studying the expression of ionotropic and metabotropic glutamate-receptors and -transporters by Affymetrix gene array analysis, followed by real-time PCR and western blot analysis. Cellular localization of glutamate transporters was investigated by fluorescence double-labeling experiments. Comparing white and gray matter areas, the expression of glutamate receptors was region-specific. Among NMDA receptor subunits, NR2A was up-regulated in the demyelinated corpus callosum (CC), whereas the metabotropic glutamate receptor mGluR2 was down-regulated in demyelinated gray matter. Glutamate-aspartate transporter (GLAST) co-localizing with GFAP(+) astrocytes was increased in both demyelinated CC and telencephalic cortex, whereas Slc1a4 transporter was up-regulated only in CC. Our data indicate that cuprizone treatment affects glutamate-receptors and -transporters differently in gray and white matter brain areas revealing particularly regulation of GLAST and Slc1a4 compared with other genes. This might have an important influence on brain-region selective sensitivity to neurotoxic compounds and the progression of demyelination as has been reported for MS and other demyelinating neurological diseases.
Collapse
Affiliation(s)
- Abolfazl Azami Tameh
- Anatomical Sciences Research Center, Kashan University of Medical Sciences, Kashan, Iran; Institute of Neuroanatomy, Faculty of Medicine, RWTH Aachen University, Aachen, Germany.
| | | | | | | | | | | |
Collapse
|
44
|
Maldonado C, Alicea D, Gonzalez M, Bykhovskaia M, Marie B. Adar is essential for optimal presynaptic function. Mol Cell Neurosci 2012; 52:173-80. [PMID: 23127996 DOI: 10.1016/j.mcn.2012.10.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 09/20/2012] [Accepted: 10/23/2012] [Indexed: 12/31/2022] Open
Abstract
RNA editing is a powerful way to recode genetic information. Because it potentially affects RNA targets that are predominantly present in neurons, it is widely hypothesized to affect neuronal structure and physiology. Across phyla, loss of the enzyme responsible for RNA editing, Adar, leads to behavioral changes, impaired locomotion, neurodegeneration and death. However, the consequences of a loss of Adar activity on neuronal structure and function have not been studied in detail. In particular, the role of RNA editing on synaptic development and physiology has not been investigated. Here we test the physiological and morphological consequences of the lack of Adar activity on the Drosophila neuromuscular junction (NMJ). Our detailed examination of synaptic transmission showed that loss of Adar increases quantal size, reduces the number of quanta of neurotransmitter released and perturbs the calcium dependence of synaptic release. In addition, we find that staining for several synaptic vesicle proteins is abnormally intense at Adar deficient synapses. Consistent with this finding, Adar mutants showed a major alteration in synaptic ultrastructure. Finally, we present evidence of compensatory changes in muscle membrane properties in response to the changes in presynaptic activity within the Adar mutant NMJs.
Collapse
Affiliation(s)
- Carolina Maldonado
- Institute of Neurobiology, Medical Sciences Campus, University of Puerto Rico, PR
| | | | | | | | | |
Collapse
|
45
|
Cisneros IE, Ghorpade A. HIV-1, methamphetamine and astrocyte glutamate regulation: combined excitotoxic implications for neuro-AIDS. Curr HIV Res 2012; 10:392-406. [PMID: 22591363 PMCID: PMC3580828 DOI: 10.2174/157016212802138832] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 04/18/2012] [Accepted: 04/18/2012] [Indexed: 02/08/2023]
Abstract
Glutamate, the most abundant excitatory transmitter in the brain can lead to neurotoxicity when not properly regulated. Excitotoxicity is a direct result of abnormal regulation of glutamate concentrations in the synapse, and is a common neurotoxic mediator associated with neurodegenerative disorders. It is well accepted that methamphetamine (METH), a potent central nervous stimulant with high abuse potential, and human immunodeficiency virus (HIV)-1 are implicated in the progression of neurocognitive malfunction. Both have been shown to induce common neurodegenerative effects such as astrogliosis, compromised blood brain barrier integrity, and excitotoxicity in the brain. Reduced glutamate uptake from neuronal synapses likely leads to the accumulation of glutamate in the extracellular spaces. Astrocytes express the glutamate transporters responsible for majority of the glutamate uptake from the synapse, as well as for vesicular glutamate release. However, the cellular and molecular mechanisms of astrocyte-mediated excitotoxicity in the context of METH and HIV-1 are undefined. Topics reviewed include dysregulation of the glutamate transporters, specifically excitatory amino acid transporter-2, metabotropic glutamate receptor(s) expression and the release of glutamate by vesicular exocytosis. We also discuss glutamate concentration dysregulation through astrocytic expression of enzymes for glutamate synthesis and metabolism. Lastly, we discuss recent evidence of various astrocyte and neuron crosstalk mechanisms implicated in glutamate regulation. Astrocytes play an essential role in the neuropathologies associated with METH/HIV-1-induced excitotoxicity. We hope to shed light on common cellular and molecular pathways astrocytes share in glutamate regulation during drug abuse and HIV-1 infection.
Collapse
Affiliation(s)
| | - Anuja Ghorpade
- University of North Texas Health Science Center, Fort Worth, TX, USA
| |
Collapse
|
46
|
Barker M, Solinski HJ, Hashimoto H, Tagoe T, Pilati N, Hamann M. Acoustic overexposure increases the expression of VGLUT-2 mediated projections from the lateral vestibular nucleus to the dorsal cochlear nucleus. PLoS One 2012; 7:e35955. [PMID: 22570693 PMCID: PMC3343051 DOI: 10.1371/journal.pone.0035955] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Accepted: 03/28/2012] [Indexed: 11/19/2022] Open
Abstract
The dorsal cochlear nucleus (DCN) is a first relay of the central auditory system as well as a site for integration of multimodal information. Vesicular glutamate transporters VGLUT-1 and VGLUT-2 selectively package glutamate into synaptic vesicles and are found to have different patterns of organization in the DCN. Whereas auditory nerve fibers predominantly co-label with VGLUT-1, somatosensory inputs predominantly co-label with VGLUT-2. Here, we used retrograde and anterograde transport of fluorescent conjugated dextran amine (DA) to demonstrate that the lateral vestibular nucleus (LVN) exhibits ipsilateral projections to both fusiform and deep layers of the rat DCN. Stimulating the LVN induced glutamatergic synaptic currents in fusiform cells and granule cell interneurones. We combined the dextran amine neuronal tracing method with immunohistochemistry and showed that labeled projections from the LVN are co-labeled with VGLUT-2 by contrast to VGLUT-1. Wistar rats were exposed to a loud single tone (15 kHz, 110 dB SPL) for 6 hours. Five days after acoustic overexposure, the level of expression of VGLUT-1 in the DCN was decreased whereas the level of expression of VGLUT-2 in the DCN was increased including terminals originating from the LVN. VGLUT-2 mediated projections from the LVN to the DCN are likely to play a role in the head position in response to sound. Amplification of VGLUT-2 expression after acoustic overexposure could be a compensatory mechanism from vestibular inputs in response to hearing loss and to a decrease of VGLUT-1 expression from auditory nerve fibers.
Collapse
Affiliation(s)
- Matthew Barker
- Department of Cell Physiology and Pharmacology, Leicester University, Leicester, United Kingdom
| | - Hans Jürgen Solinski
- Department of Cell Physiology and Pharmacology, Leicester University, Leicester, United Kingdom
| | - Haruka Hashimoto
- Department of Cell Physiology and Pharmacology, Leicester University, Leicester, United Kingdom
| | - Thomas Tagoe
- Department of Cell Physiology and Pharmacology, Leicester University, Leicester, United Kingdom
| | - Nadia Pilati
- Department of Cell Physiology and Pharmacology, Leicester University, Leicester, United Kingdom
| | - Martine Hamann
- Department of Cell Physiology and Pharmacology, Leicester University, Leicester, United Kingdom
| |
Collapse
|
47
|
Lin LH, Nitschke Dragon D, Talman WT. Collateral damage and compensatory changes after injection of a toxin targeting neurons with the neurokinin-1 receptor in the nucleus tractus solitarii of rat. J Chem Neuroanat 2012; 43:141-8. [PMID: 22414622 DOI: 10.1016/j.jchemneu.2012.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 02/23/2012] [Accepted: 02/24/2012] [Indexed: 02/02/2023]
Abstract
Injection into the nucleus tractus solitarii (NTS) of toxins that target substance P (SP) receptors ablates neurons that express neurokinin-1 (NK1) receptors, attenuates baroreflexes, and results in increased lability of arterial pressure. We and others have shown that the toxin leads to loss of neurons containing SP receptors and loss of GABAergic neurons in the NTS; but given that neither type neuron is thought to be integral to baroreflex transmission in NTS, mechanisms responsible for the cardiovascular changes remained unclear. Because NK1 receptors colocalize with N-methyl-d-aspartate (NMDA) receptors and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors in NTS and because glutamate transmission may be integral to baroreflex transmission in the NTS we hypothesized that the toxic lesions may interrupt mechanisms for glutamate transmission. Interruption of those mechanisms could be responsible for the cardiovascular effects. We tested the hypothesis by performing fluorescent immunohistochemistry, confocal microscopy and image analysis after injecting stabilized SP-SAP (SSP-SAP) unilaterally into the NTS. We assessed changes in immunoreactivity (IR) of NMDA receptor subunit 1 (NMDAR1), AMPA receptor subunit 2 (GluR2), and 3 types of vesicular glutamate transporters (VGluT) as well as IR of gamma-aminobutyric acid receptors type b (GABAb), neuronal nitric oxide synthase (nNOS), tyrosine hydroxylase (TH), and protein gene product 9.5 (PGP 9.5), a neuronal marker, in the NTS. When compared to that of the same section of the un-injected NTS, IR decreased significantly in the injected side for NMDAR1 (p<0.01), GluR2 (p<0.01), VGluT3 (p<0.01), GABAb (p<0.001), and PGP9.5 (p<0.001). In contrast, IR for VGluT1 (p<0.001), VGluT2 (p<0.001), nNOS (p<0.001), and TH (p<0.001) increased significantly. We conclude that pathologic effects following ablation of neurons with NK1 receptors in NTS may result from interruption of neurotransmission through other neurochemical systems associated with NK1 receptors-containing neurons.
Collapse
Affiliation(s)
- Li-Hsien Lin
- Department of Neurology, University of Iowa, Iowa City, IA 52242, USA
| | | | | |
Collapse
|